News: Centre WACQThttp://www.chalmers.se/sv/nyheterNews related to Chalmers University of TechnologySun, 16 May 2021 11:53:38 +0200http://www.chalmers.se/sv/nyheterhttps://www.chalmers.se/en/departments/mc2/news/Pages/Novel-thermometer-can-accelerate-the-development-of-quantum-computers.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Novel-thermometer-can-accelerate-the-development-of-quantum-computers.aspxNovel thermometer can accelerate quantum computer development <p><b><p class="MsoNormal">Researchers at Chalmers University of Technology, Gothenburg, Sweden, have developed a novel type of thermometer that can simply and quickly measure temperatures during quantum calculations with extremely high accuracy. The breakthrough provides a benchmarking tool for quantum computing of great value – and opens up for experiments in the exciting field of quantum thermodynamics.​​​</p></b></p><div><span style="background-color:initial">A key component in quantum computers are coaxial cables and waveguides – structures which guide waveforms, and act as the vital connection between the quantum processor, and the classical electronics which control it. Microwave pulses travel along the waveguides to the quantum processor, and are cooled down to extremely low temperatures along the way. The waveguide also attenuates and filters the pulses, enabling the extremely sensitive quantum computer to work with stable quantum states.  </span><br /></div> <div><br /></div> <div>In order to have maximum control over this mechanism, the researchers need to be sure that these waveguides are not carrying noise due to thermal motion of electrons on top of the pulses that they send. In other words, they have to measure the temperature of the electromagnetic fields at the cold end of the microwave waveguides, the point where the controlling pulses are delivered to the computer’s qubits. Working at the lowest possible temperature minimises the risk of introducing errors in the qubits.</div> <div><br /></div> <div>Until now, researchers have only been able to measure this temperature indirectly, with relatively large delay. Now, with the Chalmers researchers' novel thermometer, very low temperatures can be measured directly at the receiving end of the waveguide – very accurately and with extremely high time resolution.</div> <div><img src="/SiteCollectionImages/20210101-20210631/Simone%20Gasparinetti%20(1).jpg" class="chalmersPosition-FloatLeft" alt="" style="margin:5px 10px;width:180px;height:157px" /><br />&quot;Our thermometer is a superconducting circuit, directly connected to the end of the waveguide being measured. It is relatively simple – and probably the world's fastest and most sensitive thermometer for this particular purpose at the millikelvin scale,&quot; says Simone Gasparinetti, Assistant Professor at the Quantum Technology Laboratory, Chalmers University of Technology.</div> <h2 class="chalmersElement-H2"><span style="font-family:inherit;background-color:initial"><br />Im</span><span style="font-family:inherit;background-color:initial">portant for measuring quantum computer performance</span><br /></h2> <div>The researchers at the Wallenberg Centre for Quantum Technology, WACQT, have the goal to build a quantum computer – based on superconducting circuits – with at least 100 well-functioning qubits, performing correct calculations by 2030. It requires a processor working temperature close to absolute zero, ideally down to 10 millikelvin. The new thermometer gives the researchers an important tool for measuring how good their systems are and what shortcomings exist – a necessary step to be able to refine the technology and achieve their goal.</div> <div><br /></div> <div><img src="/SiteCollectionImages/20210101-20210631/PerDelsing_171101_02%20(1).jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px 10px;width:180px;height:157px" />&quot;A certain temperature corresponds to a given number of thermal photons, and that number decreases exponentially with temperature. If we succeed in lowering the temperature at the end where the waveguide meets the qubit to 10 millikelvin, the risk of errors in our qubits is reduced drastically,&quot; says Per Delsing, Professor at the Department of Microtechnology and Nanoscience, Chalmers University of Technology, and leader of WACQT.</div> <div><br /></div> <div>Accurate temperature measurement is also necessary for suppliers who need to be able to guarantee the quality of their components, for example cables that are used to handle signals down to quantum states.</div> <h2 class="chalmersElement-H2">New opportunities in the field of quantum thermodynamics</h2> <div>Quantum mechanical phenomena such as superposition, entanglement and decoherence mean a revolution not only for future computing but potentially also in thermodynamics. It may well be that the thermodynamic laws somehow change when working down at the nanoscale, in a way that could one day be exploited to produce more powerful engines, faster-charging batteries, and more.</div> <div><br /></div> <div>&quot;For 15-20 years, people have studied how the laws of thermodynamics might be modified by quantum phenomena, but the search for a genuine quantum advantage in thermodynamics is still open,&quot; says Simone Gasparinetti, who recently started his own research group and plans to contribute to this search with a novel range of experiments.</div> <div><br /></div> <div>The new thermometer can, for example, measure the scattering of thermal microwaves from a circuit acting as a quantum heat engine or refrigerator.</div> <div><img src="/SiteCollectionImages/20210101-20210631/Marco%20Scigliuzzo%20(2).jpg" class="chalmersPosition-FloatLeft" alt="" style="margin:5px 10px;width:180px;height:157px" /><br />&quot;Standard thermometers were fundamental for developing classical thermodynamics. We hope that maybe, in the future, our thermometer will be regarded as pivotal for developing quantum thermodynamics,&quot; says Marco Scigliuzzo, doctoral student at the Department of Microtechnology and Nanoscience, Chalmers University of Technology.</div> <div><br /></div> <div><br /></div> <div><strong>Read more in the scientific article in Physical Review X:</strong></div> <div><a href="https://journals.aps.org/prx/abstract/10.1103/PhysRevX.10.041054">Primary Thermometry of Propagating Microwaves in the Quantum Regime</a></div> <div><br /></div> <div><strong>More about: How the primary thermometer works</strong></div> <div><span style="background-color:initial">The </span><span style="background-color:initial">novel thermometer concept relies on the interplay between coherent and incoherent scattering from a quantum emitter driven at resonance. The emitter is strongly coupled to the end of the waveguide being tested. Thermal photons in the waveguide lead to a measurable drop in the coherently scattered signal, which is recorded continuously. In this way, the number of photons in the propagating mode of the microwave waveguides can be read – this corresponds to a temperature. The Chalmers researchers’ implementation, which uses a superconducting circuit operated at gigahertz frequencies, offers simplicity, large bandwidth, high sensitivity, and negligible power dissipation.<br /></span><span style="background-color:initial"><br /><b>More about: The Wallenberg Centre for Quantum Technology</b></span></div> <div><span style="background-color:initial"><div><a href="/en/centres/wacqt/Pages/default.aspx">The Wallenberg Centre for Quantum Technology​</a>, WACQT​, is a 12 year research center that aims to take Sweden to the forefront of quantum technology. The main project is to develop an advanced quantum computer. WACQT is coordinated from Chalmers University of Technology, and has activities also at the Royal Institute of Technology, Lund University, Stockholm University, Linköping University and Göteborg University. </div></span></div> Tue, 23 Mar 2021 07:00:00 +0100https://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/anne-lhuillier.aspxhttps://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/anne-lhuillier.aspxAnne L’Huillier wins the Max Born Award<p><b>The Optical Society, OSA, awards WACQT principal investigator, professor Anne l’Huillier, the Max Born Award for pioneering work in ultrafast laser science and attosecond physics.<div><span style="background-color:initial">​</span></div></b></p>​Anne L’Huillier, principle investigator in WACQT and professor of Atomic Physics , has been awarded the Optical Society Max Born Award 2021 “for pioneering work in ultrafast laser science and attosecond physics, realizing and understanding high harmonic generation and applying it to time-resolved imaging of electron motion in atoms and molecules.”<br /><div><span style="background-color:initial">Read more on </span><span style="background-color:initial"><a href="https://www.nano.lu.se/article/anne-lhuillier-wins-max-born-award">https://www.nano.lu.se/article/anne-lhuillier-wins-max-born-award</a></span></div>Tue, 16 Mar 2021 09:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Swedens-quantum-computer-project-shifts-up-a-gear.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Swedens-quantum-computer-project-shifts-up-a-gear.aspxSweden's quantum computer project shifts up a gear<p><b>​<span style="background-color:initial">Knut and Alice Wallenberg Foundation is almost doubling the annual budget of the research initiative Wallenberg Centre for Quantum Technology, based at Chalmers University of Technology, Sweden. This will allow the centre to shift up a gear and set even higher goals – especially in its development of a quantum computer. Two international workshops will kick-start this new phase. </span><p class="MsoNormal"><span lang="EN-US"></span>​​​​​​</p></b></p><div><span style="background-color:initial">”Quantum technology has enormous potential and it is important that Sweden has the necessary skills in the area. During the short time since the center was founded, WACQT has built up a qualified research environment, established collaborations with Swedish industry and succeeded in developing qubits with proven problem-solving ability. We can look ahead with great confidence at what they will go on to achieve,” says Peter Wallenberg Jr, Chair Knut and Alice Wallenberg Foundation.<br /></span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">Since 2018, Chalmers University of Technology has been managing a large, forward-thinking research initiative – the Wallenberg Centre for Quantum Technology (WACQT) – setting Sweden on course to global prominence in quantum technology. The main project is to develop and build a quantum computer, offering far greater computing power than today's best supercomputers.</span><br /></div> <div><span style="background-color:initial"><br /></span></div> <div>During the first three years, the quantum computer researchers within WACQT have focused first on making the basic building blocks of the quantum computer – the qubits – work as well as possible, at small scale. A milestone was reached in 2020, when they managed to solve a small part of a real-world optimisation problem with their well-functioning two-qubit quantum computer.</div> <div><h2 class="chalmersElement-H2">Increases the quality of the hundred qubits​</h2></div> <div>Now comes the time to significantly scale up the number of qubits, and increase the efforts on developing software and algorithms. At the same time, the entire research initiative is being scaled up, with <a href="https://kaw.wallenberg.org/en">Knut and Alice Wallenberg Foundation, KAW</a>, deciding to almost double WACQT's annual budget, from SEK 45 to 80 million per year for the coming four years. The investment has previously also been extended from its original ten years to twelve, and has now a total funding of at least SEK 1.3 billion including contributions from industry and the participating universities.</div> <div><br /></div> <div><img src="/SiteCollectionImages/20210101-20210631/PerDelsing_171101_02%20(1).jpg" class="chalmersPosition-FloatLeft" alt="" style="margin:5px;width:175px;height:152px" /> </div> <div><span style="background-color:initial">“It is very encouraging that KAW shows such great confidence in us. It strengthens WACQT’s research programme and gives us the opportunity to build an even better quantum computer. In terms of the number of qubits, the goal is still one hundred, but now we are aiming at one hundred really high-performance qubits,” says Per Delsing, director of WACQT and Professor at Chalmers.</span><br /></div> <div><br /></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">Calculations have shown that the performance of the final quantum computer will benefit more from increasing the quality of the individual qubits, rather than the total number of qubits. The better their quality , the more useful the final quantum computer.</span><br /></div> <div><br /></div> <div>With the increased funding, WACQT will, among other things, invest in improving the materials in the superconducting chips that constitute the qubits. Quantum states are extremely sensitive, and the slightest disturbance in the materials can impair performance. The qubits manufactured at Chalmers are already among the best in the world, so improving them entails moving the entire research field into new territory. </div> <div><br /></div> <div>“These disturbances are extremely small. It requires research just to understand what they are and which are most common. We need to study the entire manufacturing process in detail and explore new ways to eliminate disturbances in the material,” Delsing explains.</div> <h2 class="chalmersElement-H2">Will employ another 40 researchers​</h2> <div>With the increased funding, the number of researchers working in the quantum computer project can now be significantly increased. For example, a new team will be formed to study nanophotonic devices that can enable the interconnection of several smaller quantum processors into a large quantum computer. Within the next two years, the research force will be expanded by 40 people, almost double the current amount. In a first step, fifteen new postdocs will be recruited.</div> <div><br /></div> <div>“This is an ambitious recruitment in a highly competitive niche area. But our hopes are high – through previous recruitments we have attracted top talents both from Sweden and internationally. We have a unique interaction with the industry, extensive experience of superconducting circuits and an amazing clean room facility,” says Delsing.</div> <div><br /></div> <div>To mark the quantum computer project’s new, next-level development, WACQT is organising two international workshops: one on quantum software and optimisation (8–9 April), and the second on enabling technology and algorithms for quantum computing (13–14 April). Anyone curious to hear about the state of the art in quantum computing can follow the workshops online.</div> <div><br /></div> <div>“These are very exciting times in quantum computing. New steps are being taken all the time and the competition is rapidly increasing, with many countries making major investments. This investment will ensure that Sweden and Chalmers remain at the global forefront,” Delsing says.</div> <div><br /></div> <div><strong>Read more:</strong></div> <div><p class="chalmersElement-P"><span><span><a href="/en/centres/wacqt/calendar/Pages/ttp-qs.aspx" target="_blank">Quantum Software and Optimisation online workshop 8-9 April​</a><br /></span></span><a href="/en/centres/wacqt/calendar/Pages/ws%20enabling%20technology.aspx" target="_blank">Workshop on Enabling Technology and Algorithms for Quantum Computing 13-14 April</a><br /><a href="https://wacqt.se/" target="_blank">Wallenberg Centre for Quantum Technology (WACQT)</a><br /><a href="/en/news/Pages/Engineering-of-a-Swedish-quantum-computer-set-to-start.aspx" target="_blank">Engineering of a Swedish quantum computer set to start</a><span style="background-color:initial"> (initial press release from 2017)<br /></span><a href="/en/departments/mc2/news/Pages/Tiny-quantum-computer-solves-real-optimisation-problem.aspx" target="_blank">Tiny quantum computer solves real optimisation problem</a><span style="background-color:initial"> (press release from 2020)​</span></p></div> <div></div> <div><br /></div> <div><div><strong>More about: The Wallenberg Centre for Quantum Technology</strong></div> <div><a href="/en/centres/wacqt/Pages/default.aspx">The Wallenberg Centre for Quantum Technology, WACQT​</a>, is a 12 year research center that aims to take Sweden to the forefront of quantum technology. The main project is to develop an advanced quantum computer. WACQT is coordinated from Chalmers University of Technology, and has activities also at the Royal Institute of Technology, Lund University, Stockholm University, Linköping University and Göteborg University.</div></div> <div><br /></div> <div><strong>For more information, please contact:</strong></div> <div>Per Delsing, Director of Wallenberg Centre for Quantum Technology, Chalmers University of Technology, <a href="mailto:per.delsing@chalmers.se">per.delsing@chalmers.se​</a>, +46-70-308 83 17</div> <div>​<br /></div> ​Mon, 15 Mar 2021 10:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/kvantfysiker-i-kva.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/kvantfysiker-i-kva.aspxQuantum physicist elected member of the Royal Swedish Academy of Sciences<p><b><div><p class="MsoNormal" style="line-height:16.5pt"><span lang="EN" style="font-size:12pt"></span><span lang="EN-US"></span><span style="background-color:initial;font-size:16px">Göran Johansson, professor at the Department of Microtechnology and Nanoscience, has been elected member of the Royal Swedish Academy of Sciences. He thus becomes the seventh Chalmers professor in the class of physics, and the third from our department.</span></p></div> <div><span style="background-color:initial"><br /></span></div> <p class="MsoNormal" style="line-height:16.5pt"><span style="font-size:12pt;font-family:arial, sans-serif"></span></p></b></p>​<img src="/SiteCollectionImages/Institutioner/MC2/News/Göran%20Johansson%20600_900.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px;width:250px;height:375px" /><span style="background-color:initial">G</span><span style="background-color:initial">öran</span><span style="background-color:initial"></span><span style="background-color:initial"></span><span style="background-color:initial"></span><span style="background-color:initial"> Johansson is head of Applied Quantum Physics Laboratory and was elected at the Academy's meeting on 13 January as a member of the Class for physics.</span><div><br /></div> <div>&quot;I feel honored and actually I’m a bit shocked. I hope that I will be able to contribute with my expertise in quantum technology and my curiosity in other research areas. The Royal Swedish Academy of Sciences is a heavy referral body in the Swedish research community and, among other things, does a very important work with the Nobel Prizes.” </div> <div><br /></div> <div>According to the website, the Royal Swedish Academy of Sciences is an independent organisation that aims to promote the sciences and strengthen their influence in society. The Academy also rewards outstanding research achievements through numerous prizes – the most famous are, of course, the Nobel Prizes in Chemistry and Physics. Being elected as a member of the Academy is seen as an exclusive recognition for efforts in research.</div> <div> </div> <div>An overall goal of Göran's research is to understand how quantum physics works in nature and how to take advantage of quantum physical effects in practical applications. Among other things, he studies the dynamic Casimir effect, which describes how photons are created out of vacuum when a mirror accelerates and moves close to the speed of light.</div> <div><br /></div> <div>A more applied question is how to best build a quantum computer. The Quantum bit, the smallest information carrier in a quantum computer, can have both the value 0 and 1 at the same time and can therefore provide a computational capacity much larger than today's fastest supercomputers. For example, a quantum computer could study complex molecular structures in medical research and provide new drugs. It could also give us completely new opportunities to see structures in large data sets in order to find better solutions to difficult optimization problems, such as traffic planning.</div> <div><br /></div> <div><div><a href="http://www.kva.se/" style="background-color:rgb(255, 255, 255)"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" /></a>Read more about the Royal Swedish Academy of Sciences on <a href="http://www.kva.se/">the Academy's website</a>. </div> <div><a href="http://www.kva.se/" style="background-color:rgb(255, 255, 255)"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" /></a>Read more about Göran in the article  <a href="/en/centres/gpc/news/Pages/Goran-wants-to-build-Swedens-first-quantum-computer.aspx">&quot;Göran wants to build Sweden's first quantum computer&quot;​</a></div></div> <div><br /></div> <div>Text: Susannah Carlsson<br />Photo: Kerstin Jönsson</div> <div><div></div> <div><br /></div> </div>Wed, 20 Jan 2021 17:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Tiny-quantum-computer-solves-real-optimisation-problem.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Tiny-quantum-computer-solves-real-optimisation-problem.aspxTiny quantum computer solves real optimisation problem<p><b><p class="MsoNormal">Quantum computers have already managed to surpass ordinary computers in solving certain tasks – unfortunately, totally useless ones. The next milestone is to get them to do useful things. Researchers at Chalmers University of Technology, Sweden, have now shown that they can solve a small part of a real logistics problem with their small, but well-functioning quantum computer.​<br /></p></b></p><div><div><span style="font-size:14px">Interest in building quantum computers has gained considerable momentum in recent years, and feverish work is underway in many parts of the world. In 2019, Google's research team made a major breakthrough when their quantum computer managed to solve a task far more quickly than the world's best supercomputer. The downside is that the solved task had no practical use whatsoever – it was chosen because it was judged to be easy to solve for a quantum computer, yet very difficult for a conventional computer.<br /></span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="background-color:initial">T</span><span style="background-color:initial">herefore, an important task is now to find useful, relevant problems that are beyond the reach of ordinary computers, but which a relatively small quantum computer could </span><span style="background-color:initial">solve.</span><br /></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px"><img src="/SiteCollectionImages/Centrum/WACQT/PIs/GiuliaFerrini_180109_02%20kvadrat.jpg" class="chalmersPosition-FloatRight" alt="Giulia Ferrini" style="margin:5px;width:180px;height:180px" />“We want to be sure that the quantum com​puter we are developing can help solve relevant problems early on. Therefore, we work in close collaboration with industrial companies”, says theoretical physicist Giulia Ferrini, one of the leaders of Chalmers University of Technology’s quantum computer project, which began in 2018.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">Together with Göran Johansson, Giulia Ferrini led the theoretical work when a team of researchers at Chalmers, including an industrial doctoral student from the aviation logistics company Jeppesen, recently showed that a quantum computer can solve an instance of a real problem in the aviation industry.</span></div> <h2 class="chalmersElement-H2"><span>The algorithm proven on two qubits</span></h2> <div><span style="font-size:14px">All airlines are faced with scheduling problems. For example, assigning individual aircraft to different routes represents an optimisation problem, one that grows very rapidly in size and complexity as the number of routes and aircraft increases.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">Researchers hope that quantum computers will eventually be better at handling such problems than today's computers. The basic building block of the quantum computer – the qubit – is based on completely different principles than the building blocks of today's computers, allowing them to handle enormous amounts of information with relatively few qubits. </span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">However, due to their different structure and function, quantum computers must be programmed in other ways than conventional computers. One proposed algorithm that is believed to be useful on early quantum computers is the so-called Quantum Approximate Optimization Algorithm (QAOA).</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">The Chalmers research team has now successfully executed said algorithm on their quantum computer – a processor with two qubits – and they showed that it can successfully solve the problem of assigning aircraft to routes. In this first demonstration, the result could be easily verified as the scale was very small – it involved only two airplanes.</span></div> <h2 class="chalmersElement-H2"><span>Potential to handle many aircraft</span></h2> <div><span style="font-size:14px">With this feat, the researchers were first to show that the QAOA algorithm can solve the problem of assigning aircraft to routes in practice. They also managed to run the algorithm one level further than anyone before, an achievement that requires very good hardware and accurate control.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px"><img src="/SiteCollectionImages/Centrum/WACQT/PIs/JonasBylander_171101_kvadrat.jpg" class="chalmersPosition-FloatLeft" alt="Jonas Bylander" style="margin:5px;width:180px;height:180px" /></span></div> <div><span style="font-size:14px">​“We have shown that we have the ability to map relevant problems onto our quantum processor. We still have a small number of qubits, but they work well. Our plan has been to first make everything work very well on a small scale, before scaling up,” says Jonas Bylander, senior researcher responsible for the experimental design, and one of the leaders of the project of building a quantum computer at Chalmers. </span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">The theorists in the research team also simulated solving the same optimisation problem for up to 278 aircraft, which would require a quantum computer with 25 qubits.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">“The results remained good as we scaled up. This suggests that the QAOA algorithm has the potential to solve this type of problem at even larger scales,” says Giulia Ferrini.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">Surpassing today’s best computers would, however, require much larger devices. The researchers at Chalmers have now begun scaling up and are currently working with five quantum bits. The plan is to reach at least 20 qubits by 2021 while maintaining the high quality. </span></div></div> <div><span style="font-size:14px"><br /></span></div> <strong>Text:</strong> Ingela Roos<br /><strong>Portrait pictures: </strong>Johan Bodell<br /><p></p> <p class="MsoNormal"><span style="background-color:initial"><br /></span></p> <p class="MsoNormal"><span lang="EN-GB">The research results have been published in two articles in <em>Physical Review Applied</em>:</span></p> <p class="MsoNormal"><span lang="sv"><span lang="EN-GB"><a href="https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.14.034010"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Improved Success Probability with Greater Circuit Depth for the Quantum Approximate Optimization Algorithm</a><br /></span></span><a href="https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.14.034009"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" /><span lang="EN-GB">Applying the Quantum Approximate Optimization Algorithm to the Tail-Assignment Problem</span></a><span style="background-color:initial"> </span></p> <h2 class="chalmersElement-H2"><span>More about: The Swedish quest for a quantum computer</span></h2> <p class="MsoNormal"><span style="font-size:14px">The research is part of the Wallenberg Centre for Quantum Technology (WACQT), a twelve-year, billion-dollar investment with two main purposes: to develop Swedish expertise in quantum technology, and to build a useful quantum computer with at least one hundred quantum bits. The research centre is mainly funded by the Knut and Alice Wallenberg Foundation.</span><br /><span style="background-color:initial"></span></p> <h2 class="chalmersElement-H2"><span lang="EN-GB">Read more:</span></h2> <p class="MsoNormal"><span lang="sv"><a href="/en/news/Pages/Engineering-of-a-Swedish-quantum-computer-set-to-start.aspx"><span lang="EN-GB">Engineering of a Swedish quantum computer set to start</span></a></span><span lang="EN-GB"> (initial press release from 2017)</span><span lang="EN-GB"><br /></span><span lang="sv" style="background-color:initial"><a href="/en/centres/wacqt/discover/Pages/default.aspx"><span lang="EN-GB">Discover quantum technology</span></a></span><span lang="EN-GB" style="background-color:initial"> (introduction to quantum technology)<br /></span><span lang="sv" style="background-color:initial"><a href="/en/centres/wacqt/discover/Pages/Quantum-computing.aspx"><span lang="EN-GB">Quantum computing</span></a></span><span lang="EN-GB" style="background-color:initial"> (introduction to quantum computing)<br /></span><span lang="EN-GB"><a href="/en/centres/wacqt/Pages/default.aspx">Wallenberg Centre for Quantum Technology (WACQT)</a><br /></span><span lang="sv" style="background-color:initial"><a href="/en/centres/wacqt/research/Pages/Research-in-quantum-computing-and-simulation.aspx"><span lang="EN-GB">Research in quantum computing and simulation</span></a></span><span lang="EN-GB" style="background-color:initial"> (about quantum computing research within WACQT)</span><span style="background-color:initial"> </span></p> <h2 class="chalmersElement-H2"><span lang="EN-GB">For more information, please contact:</span></h2> <p class="MsoNormal"><span style="background-color:initial;font-size:14px">Giulia Ferrini, Assistant Professor in Applied Quantum Physics, Chalmers University of Technology, <a href="mailto:ferrini@chalmers.se">ferrini@chalmers.se</a>, +46 31 772 6417<br />Jonas Bylander, Associate Professor in Quantum Technology, Chalmers University of Technology, <a href="mailto:jonas.bylander@chalmers.se">jonas.bylander@chalmers.se​</a>, +46 31 772 5132</span><span style="background-color:initial">​​​</span>​ ​</p>Thu, 17 Dec 2020 09:00:00 +0100https://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Universal-Gate-Set-for-Continuous-Variable-Quantum-Computation-with-Microwave-Circuits.aspxhttps://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Universal-Gate-Set-for-Continuous-Variable-Quantum-Computation-with-Microwave-Circuits.aspxUniversal Gate Set for Continuous-Variable Quantum Computation with Microwave Circuits<p><b></b></p><p class="chalmersElement-P"><span lang="EN-US" style="background-color:initial">Researchers from WACQT, Chalmers has toghether with researchers from RWTH and Queen’s University </span><span style="background-color:initial">presented a novel proposal for harnessing properties of a recently developed superconducting circuit element in order to realize long-standing goals in continuous-variable quantum computing. </span><span style="background-color:initial">For almost two decades</span><span style="background-color:initial"> this has primarily been pursued in the context </span><span style="background-color:initial">of optical systems. </span></p> <div> </div> <div> </div> <div> </div> <p class="chalmersElement-P"><span style="background-color:initial">The work heralds further research in an area that could be referred to as “continuous-variable – noisy intermediate-scale quantum” (CV-NISQ) algorithms. </span></p> <p class="chalmersElement-P"><strong style="background-color:initial">Authors and affiliations:</strong><br /></p> <p class="chalmersElement-P"><span style="background-color:initial">Timo Hillmann</span><sup style="background-color:initial">1,2</sup><span style="background-color:initial">, Fernando Quijandría</span><sup style="background-color:initial">1</sup><span style="background-color:initial">, Göran Johansson</span><sup style="background-color:initial">1</sup><span style="background-color:initial">, Alessandro Ferraro</span><sup style="background-color:initial">3</sup><span style="background-color:initial">, Simon​e Gasparinetti</span><sup style="background-color:initial">1</sup><span style="background-color:initial">, and Giulia Ferrini</span><sup style="background-color:initial">1</sup></p> <p class="chalmersElement-P"><span style="background-color:initial">Phys. Rev. Lett. 125, 160501 – </span><span style="background-color:initial">Published 12 October 2020</span><br /></p> <div></div> <div></div> <div></div> <p class="chalmersElement-P"><sup></sup></p> <p class="chalmersElement-P"><a href="https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.160501" target="_blank"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" /><span style="background-color:initial">Read the article in Physical Re</span></a><span style="background-color:initial"><a href="https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.160501" target="_blank">view Letters</a></span></p> <p class="chalmersElement-P"><span style="font-size:10.5px;vertical-align:super;background-color:initial">1/ Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology, SE-412 96 Gothenburg, Sweden<br /></span><span style="font-size:10.5px;vertical-align:super;background-color:initial">2/ Institut für Theorie der Statistischen Physik, RWTH Aachen, 52056 Aachen, Germany<br /></span><span style="font-size:10.5px;vertical-align:super;background-color:initial">3/ Centre for Theoretical Atomic, Molecular and Optical Physics, Queen’s University Belfast, Belfast BT7 1NN, United Kingdom​</span></p> <div> </div> <p class="chalmersElement-P"><br /></p> <div> </div> <div> </div> <div> </div> <p class="chalmersElement-P"><br /><span style="font-size:14px"></span></p> <div> </div> <div> </div> <div> </div> <p class="chalmersElement-P"></p> <div> </div> <div> </div> <div> </div> <p class="chalmersElement-P"><span lang="EN-US"></span></p> <div> </div> <div> </div> <div> </div> <p class="chalmersElement-P"> </p>Fri, 06 Nov 2020 00:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Electron–spin-dynamics-studied-on-their-natural-timescale.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Electron%E2%80%93spin-dynamics-studied-on-their-natural-timescale.aspxElectron–spin dynamics studied on their natural timescale<p><b>​<span>With the help of extremely short light pulses and coincidence technology, researchers from several Swedish universities have succeeded in following the dynamic process of when the electron's spin – its rotation around its own axis – controls how an atom absorbs light. Göran Wendin, at the Department of Microtechnology and Nanoscience – MC2, at Chalmers and Raimund Feifel, at the Department of Physics at the University of Gothenburg, are two of the contributors. The new results were recently published in the scientific journal Nature Communications.<span style="display:inline-block"></span></span></b></p><div><img src="/SiteCollectionImages/Institutioner/MC2/News/GoranWendin_171101_01_350x305.jpg" class="chalmersPosition-FloatRight" alt="Picture of Göran Wendin." style="margin:5px" />Professor Göran Wendin (to the right) is one of the driving forces within the Wallenberg Centre for Quantum Technology (WACQT), which is led by Chalmers and aims to build a Swedish quantum computer within twelve years. He is involved in several research projects, including this, financed by Knut and Alice Wallenberg Foundation (KAW).</div> <div>&quot;In fact, my contribution goes all the way back to my doctoral thesis from 1972 which explained the photo absorption cross section of the 4d-shell in xenon in the range 70-140 eV, studied by the present KAW collaboration,&quot; explains Göran Wendin.</div> <div> </div> <div>In the new study, the researchers have used attosecond light pulses and coincidence techniques to follow – in real time – how the electron spin (i.e. the angular momentum of the electron around its own axis) influences the absorption of a photon in a  many-electron quantum system, the xenon atom. An attosecond is a billionth of a billionth of a second.</div> <div> </div> <div>The study is using xenon, a heavy rare gas element that exists in small amounts in the atmosphere of the Earth. It is known to absorb soft x-rays of specific wavelength unusually efficiently. </div> <div>Physicists have named the effect a giant resonance and explained that it is caused by a strong collective response of the electron cloud when the atom is exposed to the x-rays. Especially intriguing is that the electron spin has a pronounced effect on the light absorption in this system.</div> <div> </div> <div>The present analysis combines precision in both time and energy to show that the strong absorption is explained by an excited state living less than 50 attoseconds. The influence of the electron spin, however, is due to a ten times longer-lived nearby state, which can be reached by a change of electron spin (called spin flip). </div> <div>The spin-flipped state serves as a switch and determines the state of the remaining ion. The results provide new insight into the complex electron-spin dynamics of photo-induced phenomena and might be of considerable interest to applied science such as spintronics.</div> <div> </div> <div>Photo of Göran Wendin: Johan Bodell</div> <div> </div> <h3 class="chalmersElement-H3">Read the article in Nature Communications &gt;&gt;&gt; </h3> <div><a href="https://www.nature.com/articles/s41467-020-18847-1" target="_blank">www.nature.com/articles/s41467-020-18847-1 </a></div> <div> </div> <h3 class="chalmersElement-H3">More information &gt;&gt;&gt;</h3> <div>Anne L’Huillier, Department of Physics, Division of Atomics Physics, The Lund Attosecond Science Center (LASC), Lund University, 0705-317529, anne.lhuillier@fysik.lth.se</div> <div>Eva Lindroth, Department of Physics, Stockholm University, 0736-795034, eva.lindroth@fysik.su.se</div> <div>Göran Wendin, Quantum Technology Laboratory, Wallenberg Centre for Quantum Technology (WACQT), Department of Microtechnology and Nanoscience – MC2, Chalmers, 031-7723189, goran.wendin@chalmers.se</div> <div>Raimund Feifel, Department of Physics, University of Gothenburg, 0708-381689, raimund.feifel@physics.gu.se</div> <h3 class="chalmersElement-H3">More background &gt;&gt;&gt;</h3> <div>Inspired by his supervisor, legendary Chalmers Professor Stig Lundqvist (1925-2000), Göran Wendin in his thesis applied the many-body theories developed for collective excitations in atomic nuclei to the electron dynamics in heavy atoms. The point was that independent-electron models did not work – it was all pretty collective, and it explained the experimental data from the pioneering work with synchrotron radiation. Actually, Wendin was the one who in 1973 introduced the name &quot;giant dipole resonance&quot; to describe the phenomenon. </div> <div> </div> <div>While working in France 1981-83, Göran Wendin came in contact with Anne L’Huillier at the research institute Commissariat à l’Energie Atomique (CEA) in Saclay, France. Anne was doing her PhD work in the pioneering high-intensity laser group, and she wanted to do calculations for multiphoton ionization of rare-gas atoms, including xenon. Wendin became her theory supervisor, and they collaborated during the following 5 years and published a number of papers together. </div> <div> </div> <div>After that, Anne L’Huillier took off and became one of the world-leading experimentalists in the field, and she became deeply involved in the development to understand and make use of high-harmonic radiation for attosecond spectroscopy. The Nobel Prize for this kind of work was awarded to Gérard Mourou and Donna Strickland in 2018. </div> <div><br /><a href="/en/centres/gpc/activities/lisemeitner"><span>Professor Anne L’Huillier is also honored with the Gothenburg Lise Meitner Award 2020, which is awarded to scientists who made breakthrough discoveries in p​</span>hysics.​</a><br /></div> <div><br /></div> <div>If one sends intense infrared femtosecond laser pulses on a metal substrate, one can generate a comb of up to 100 overtones with 2 eV distance, covering a range of 200 eV, including the region of the xenon giant resonance. With these experiments one has a stopwatch ticking with attosecond resolution, meaning that one can follow electrons on their flight out of the atom.</div> <div> </div> <div>Related work that Göran Wendin did around 1975-85 had analyzed the giant resonance in term of atomic effective potentials, and that turned out to be very useful when relating the theoretical calculations of Eva Lindroth and her group at Stockholm University to experiment. The good old models for collective excitations – &quot;atomic plasmons&quot; – still provide the background for understanding the results of modern attacks on the atoms with optical and free-electron lasers.</div>Wed, 04 Nov 2020 09:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Giant-atoms-merge-quantum-processing-and-communication.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Giant-atoms-merge-quantum-processing-and-communication.aspxGiant atoms merge quantum processing and communication<p><b>​<span>Researchers at Chalmers University of Technology in Sweden and MIT in the US, among others, have demonstrated a new quantum-computing architecture that makes it possible to both perform quantum computations and communicate quantum information between distant parts of the quantum processor, all with low losses. The results were recently published in the renowned scientific journal Nature.<span style="display:inline-block"></span></span></b></p><img src="/SiteCollectionImages/Institutioner/MC2/News/anton_IMG_8889_350x305.jpg" alt="Picture of Anton Frisk Kockum." class="chalmersPosition-FloatRight" style="margin:5px" />&quot;We showed that quantum bits can communicate through a waveguide without the quantum information being lost&quot;, says Anton Frisk Kockum (to the right), researcher at the Applied Quantum Physics Laboratory at the Department of Microtechnology and Nanoscience – MC2, at Chalmers, and one of the authors of the article.<br /><br />A challenge for scaling up quantum computers is to enable communication between quantum bits (qubits) that are far apart. Coupling qubits to a long waveguide is usually detrimental, since it provides a channel through which quantum information can leak out. The solution the researchers found was to use “giant atoms”, a new regime of light-matter interactions.<br /><br />“Natural atoms are usually much smaller than the wavelength of the light they interact with. However, an experiment in the group of Professor Per Delsing at Chalmers in 2014 showed that an artificial atom made from superconducting circuits can connect to a waveguide at multiple points spaced wavelengths apart. When calculating how two such giant atoms would behave, we found that interference effects due to emission from the multiple coupling points could prevent the atoms from decaying into the waveguide, but still allow them to talk to each other via the waveguide. This was now demonstrated in the experiment carried out at MIT”, explains Anton Frisk Kockum.<br /><br />The researchers used the interference effects of the giant atoms to demonstrate both that the individual atoms could be protected from losing quantum information into the waveguide and that the two atoms could be entangled, with 94% fidelity, through their protected interaction via the waveguide. <br /><br />This is the first time that anyone has even reported a number for the fidelity of a two-qubit operation with qubits strongly coupled to a waveguide, since the fidelity for such an operation would be low if the qubits were not giant. The ability to perform high-fidelity quantum-computing operations on qubits coupled to a waveguide creates exciting new opportunities. <br />“It is now possible to prepare a complex quantum state in the qubits, and then quickly adjust the interference effect in the giant atoms to turn on the coupling to the waveguide and emit this quantum state as photons that can travel a long distance”, says Anton Frisk Kockum.<br /><br />The study is a collaboration between scientists from Chalmers (the theoretical part), MIT, and the research institution RIKEN in Japan. From Chalmers, Anton Frisk Kockum contributed.<br /><br />The work was partly supported by the Knut and Alice Wallenberg Foundation and The Swedish Research Council. The experiments were performed at the Research Laboratory for Electronics at MIT.<br /><br />Photo of Anton Frisk Kockum: Michael Nystås<br />Illustration: Philip Krantz, Krantz NanoArt<br /><br /><strong>Contact:</strong><br />Anton Frisk Kockum, Researcher, Applied Quantum Physics Laboratory, Department of Microtechnology and Nanoscience – MC2, Chalmers University of Technology, anton.frisk.kockum@chalmers.se<br /><br /><strong>Read the article in Nature &gt;&gt;&gt;</strong><br /><a href="https://doi.org/10.1038/s41586-020-2529-9">Waveguide quantum electrodynamics with superconducting giant artificial atoms</a><br /><br /><a href="https://research.chalmers.se/en/project/?id=9216">Read more about the research project</a> &gt;&gt;&gt;<br /><br /><strong>Further reading &gt;&gt;&gt;</strong><br /><a href="https://science.sciencemag.org/content/346/6206/207">Propagating phonons coupled to an artificial atom</a>. Gustafsson et al., Science 346, 207 (2014)<br /><a href="https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.140404">Decoherence-Free Interaction between Giant Atoms in Waveguide Quantum Electrodynamics</a>. Kockum et al., Physical Review Letters 120, 140404 (2018)<br /><br /><a href="https://news.mit.edu/2020/giant-atoms-quantum-processing-communication-0729">Press release from MIT</a> &gt;&gt;&gt;Wed, 02 Sep 2020 09:00:00 +0200https://www.chalmers.se/en/departments/mc2/news/Pages/Organizes-exclusive-student-conference-in-quantum-technology.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Organizes-exclusive-student-conference-in-quantum-technology.aspxOrganizes exclusive student conference in quantum technology<p><b>​<span>Participants from some 30 countries are expected to attend Berlin when the Quantum Future Academy 2020 (QFA2020) is organized on 1-7 November. The event is coordinated from Chalmers with Professor Göran Wendin at the forefront. Now he is chasing top Swedish students for the conference.<span style="display:inline-block"></span></span></b></p><img src="/SiteCollectionImages/Institutioner/MC2/News/GoranWendin_171101_01_350x305.jpg" alt="Picture of Göran Wendin" class="chalmersPosition-FloatRight" style="margin:5px" />Göran Wendin, to the right, is one of the driving forces within the Wallenberg Centre for Quantum Technology (WACQT), which is led by Chalmers and aims to build a Swedish quantum computer within twelve years. At the moment, however, he is fully busy with the QFA2020 management.<br />&quot;It is an extensive job with a lot of work, but also a lot of fun,&quot; he says in a pause.<br /><br />The assignment comes directly from the German research institute VDI Technologiezentrum [VDITZ] in Düsseldorf, which is the headquarters of the EU's research flagship on quantum technology, worth one billion euros, launched in autumn 2018.<br /><br />The idea of ​​QFA2020 is to offer European top students in the field of quantum technology an opportunity to gain new knowledge and new contacts in order to develop future commercial applications of the technology.<br />Similar events have been held four times before, then at the national level in Germany and France. Now, QFA is opening up and turning it into a major European education conference with participants from 30 countries.<br />&quot;One of the aims is to raise the understanding of quantum technology as a matter for Europe as a whole. We want to help create a sustainable network of young researchers,&quot; says Göran Wendin.<br /><br />Each participating country selects two students during the late summer who can travel to Germany completely free of charge in November. Travel, accommodation and living are fully reimbursed.<br /><br />QFA2020 will take place in Berlin. However, Göran Wendin points out that the organizers are closely following the development of the corona pandemic, and that all safety procedures will be followed.<br />&quot;All participants will receive detailed information in good time about any changes,&quot; he says.<br /><br />The application is open until 24 July for all interested students at the bachelor's or master's level with basic knowledge in quantum mechanics. In Sweden, the winners will be presented at a digital workshop at Chalmers in mid-September, where all applicants will present their ideas.<br /><br />The conference week in Berlin in November has a packed content. It will include study visits to companies and research laboratories, lectures, meetings with researchers, politicians and entrepreneurs, workshops and even cultural activities.<br />&quot;We can promise an exciting and exclusive week in Berlin,&quot; concludes Göran Wendin.<br /><br />Text: Michael Nystås<br />Photo: Johan Bodell<br /><br /><strong>Contact:</strong><br />Göran Wendin, Professor, Quantum Technology Laboratory, Wallenberg Centre for Quantum Technology (WACQT), Department of Microtechnology and Nanoscience <span>–<span style="display:inline-block"></span></span> MC2, Chalmers, goran.wendin@chalmers.se<br /><br /><div><span><strong>Read more about Quantum Future Academy 2020 (QFA2020) &gt;&gt;&gt;</strong><br /><a href="/en/centres/wacqt/qfa2020">www.chalmers.se/en/centres/wacqt/qfa2020</a> and also<br /><a href="https://www.quantentechnologien.de/event/quantum-future-academy-2020.html">www.quantentechnologien.de/event/quantum-future-academy-2020.html</a> <br /><br /><strong><a href="/en/centres/wacqt">Read more about Wallenberg Centre for Quantum Technology (WACQT)</a> &gt;&gt;&gt;</strong><br /><br /><a href="https://qt.eu/">Läs mer om Read more about the EU flagship in quantum technology </a>&gt;&gt;&gt;<span style="display:inline-block"></span></span><br /></div>Fri, 03 Jul 2020 09:00:00 +0200https://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Quantum-structures-enable-deep-tissue-imaging-of-blood-oxygenation.aspxhttps://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Quantum-structures-enable-deep-tissue-imaging-of-blood-oxygenation.aspxQuantum structures enable deep tissue imaging of blood oxygenation<p><b>​​<span style="font-size:14px"><span></span><span style="background-color:initial">Imaging of the blood oxygenation inside the body would be a useful tool for fast diagnosis of conditions like stroke and heart failure. However, it has so far been prevented by the fact that body tissue scatters light in all directions. A research team within the Wallenberg Centre for Quantum Technology now make use of a crystal with tailored quantum structure to solve the problem.</span></span><div><span style="background-color:initial"><br /></span></div></b></p>​<span style="background-color:initial;font-size:14px">More than 30 % of the patients seeking emergency care have symptoms related to reduced blood oxygenation, possibly indicating stroke, heart failure or similar conditions. Therefore, it would be advantageous to be able to image the oxygenation in the body. It is known that deoxygenated blood absorbs red light of a specific wavelength (700 nanometres) to a much greater extent than oxygenated blood. Measuring the light absorption at that wavelength can thus reveal the oxygenation level. Unfortunately, body tissue scatters the light in all directions, making it impossible to tell where the absorption took place.</span><span></span><div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">A research team within the Wallenberg Centre for Quantum Technology (WACQT) now tries to solve this problem by pointing an ultrasound pulse to the location to be measured. The ultrasound shifts the wavelength of the light by a small amount, and by analyzing the wavelength-shifted light for different positions of the ultrasound pulse, they expect to be able to form an image of the oxygenation level. In order to filter out the tiny amount of wavelength-shifted light from the much stronger unshifted light, they use a crystal with a specific quantum structure designed by the Quantum Information Group at Lund University. The crystal strongly suppresses light at the unshifted wavelength – and also slows down the shifted light to just a few kilometres per second.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">“This means it comes out long after any remaining unshifted light, and effectively can be distinguished from it,” says principal investigator Stefan Kröll.</span></div> <div><span style="font-size:14px">In this way, the team has managed to achieve measurements almost free from background noise, as described in an <a href="https://www.osapublishing.org/boe/abstract.cfm?uri=boe-10-11-5565" target="_blank">article in Biomedical Optics Express​</a>. The technique is developed by industrial PhD student David Hill at the medical start-up company SpectraCure AB together with the Quantum Information Group at Lund University.</span></div> <div><br /></div> Fri, 15 May 2020 10:00:00 +0200https://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Small-scale-demonstration-of-useful-quantum-algorithm.aspxhttps://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/Small-scale-demonstration-of-useful-quantum-algorithm.aspxSmall-scale demonstration of useful quantum algorithm<p><b>​<span style="font-size:14px"><span style="background-color:initial">Being able to solve a useful problem on a quantum computer – and ideally much faster than on a conventional computer – is future milestone that many researchers dream of. Researchers within Wallenberg Centre for Quantum Technology (WACQT) have now successfully demonstrated a quantum algorithm which represents a small instance of a flight optimization problem.</span></span></b></p>​<span style="background-color:initial;font-size:14px">A team of WACQT researchers, more specifically an industrial PhD student from the air logistics company Jeppesen together with quantum computing experimentalists and theorists, have now successfully demonstrated a quantum algorithm which represents a small instance of a flight optimization problem. The algorithm was run on WACQT’s superconducting two-qubit processor. In this first demonstration, the result could easily be verified as the instance of the solved problem was very small – it involved only two airplanes.</span><span></span><div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">“We have shown that the so-called Quantum Approximate Optimization Algorithm works in practice and that we have the ability to map useful problems onto our quantum processor. We have few qubits, but they work really well. The challenge is now to maintain the performance as we scale up”, says experimentalist Jonas Bylander.</span></div> <div><span style="font-size:14px"><br /></span></div> <div><span style="font-size:14px">The team is first to have managed to run the Quantum Approximate Optimization Algorithm to its second level, an achievement which requires really good hardware and accurate control of the hardware. The resulting scientific paper is available as a <a href="https://arxiv.org/abs/1912.10495" target="_blank">pre-print at arxiv.org​</a>.</span></div> <div>​<br /></div> Fri, 15 May 2020 00:00:00 +0200https://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/WACQT-is-enlarged-and-extended.aspxhttps://www.chalmers.se/en/centres/wacqt/news/Pages/nyheter/WACQT-is-enlarged-and-extended.aspxWACQT is enlarged and extended<p><b>​With an additional investment of 395 MSEK, the Knut and Alice Wallenberg Foundation increases the annual budget and adds two extra years to Wallenberg Centre for Quantum Technology (WACQT). This allows the centre to raise the goals, among other things for its quantum computer project.</b></p>​<span style="background-color:initial;font-size:14px">WACQT was originally planned for ten years and mainly financed with a 600 MSEK donation from the Knut and Alice Wallenberg foundation (KAW). However, in November 2019 KAW decided to allocate money to increase the budget for the remaining years with 15 MSEK per year, and also to extend the duration to 12 years, that is through 2029. </span><div><span style="background-color:initial">With the enlarged annual budget, WACQT will be able to:</span><div><ul><li><span style="font-size:14px">invest more in developing better materials for qubits</span></li> <li><span style="font-size:14px">invest more in quantum communication in order to be able to compete in the European quantum communication infrastructure,</span></li> <li><span style="font-size:14px">increase industrial participation by additional industrial PhD students,</span></li> <li><span style="font-size:14px">invest more in quantum computer software, and</span></li> <li><span style="font-size:14px">provide larger startup packages for newly recruited experimentalists.</span></li></ul></div> <div><span style="font-size:14px">The two additional years will allow WACQT to:</span></div> <div><ul><li><span style="font-size:14px">develop a more advanced quantum computer with well above 100 qubits,</span></li> <li><span style="background-color:initial">take better care of innovations,</span></li> <li><span style="font-size:14px">improve the education in quantum technology, and</span></li> <li><span style="font-size:14px">push to start a bachelor’s programme in quantum technology.</span></li></ul></div> <div><span style="font-size:14px">The WACQT management is now working on a formal re-application to KAW, which hopefully will be granted for the next four years. The decision will be taken in March 2021.</span></div> <div><br /></div> </div>Fri, 15 May 2020 00:00:00 +0200https://www.chalmers.se/en/departments/mc2/news/Pages/Big-breakthrough-for-quantum-computers.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Big-breakthrough-for-quantum-computers.aspxBig breakthrough for quantum computers<p><b>​Researchers at Google have for the first time succeeded in solving a problem that is beyond the reach of a regular computer with a quantum computer. In just minutes, their quantum computer performed a computational task that, according to the researchers, would have taken more than ten thousand years for a powerful supercomputer. Göran Johansson, one of the leaders of Chalmers quantum computer project, sees this as a major milestone.</b></p><div><span style="background-color:initial"><strong>How did you feel when you heard of the news?</strong></span><br /></div> <div>“I felt very happy! I knew that Google's research team was starting to get results with their 53-qubit quantum computer Sycamore, but that they have now managed to get such good reliability in their operations that they can perform this kind of calculation – it's a fantastic breakthrough!”</div> <div><br /></div> <div><strong>What lies behind the breakthrough?</strong></div> <div>“Sycamore is quite similar to Google's previous quantum computers in its structure. The breakthrough rather results from careful design of the hardware and software used to control the chip and a thorough analysis of which computational task to choose.”</div> <div><br /></div> <div><strong>Does this mean that quantum computers now outperform regular computers in general?</strong></div> <div>“No, absolutely not. The research team has shown that their quantum computer can solve a single calculation task better than a regular computer. The solved task is completely useless, it was chosen solely because it was judged to be easy to solve for a quantum computer but very difficult for a conventional one. But as quantum computers evolve, they will outperform conventional computers in more and more types of tasks.”</div> <div><br /></div> <div><strong>IBM criticizes Google’s calculations and states that their best supercomputer could solve the task in less than three days. What do you think about that?</strong></div> <div>“If that is the case, it would still be the first time a quantum computer performs something that requires the full capacity of the world's largest supercomputer, for almost three whole days, to reproduce. Whether it's ten thousand years or three days, I see the achievement of Google’s team as a very important step forward.”</div> <div><br /></div> <div><strong>What does this breakthrough mean to Chalmers quantum computer project?</strong></div> <div>“We are aiming for a quantum computer with one hundred well-functioning qubits, and Google has now shown that it is possible to create over fifty qubits that operate at over 99 percent reliability. It is incredibly inspiring and motivating!”</div> <div><br /></div> <div><strong>How does your quantum computer compare to Google’s?</strong></div> <div>“We use the same basic building blocks – superconducting circuits – as Google. So far, we are working, completely according to our plan, with a chip with only two qubits. Our strategy is to first get it to work really, really well on a small scale. For example, Google's qubits have an average lifetime of 16 microseconds, while we have over 80 microseconds. The longer the lifetime, the more computational operations you can do. On the other hand, Google has managed to reach significantly faster operations than we have, but we are working at getting really good at that as well. Then we will start to scale up in fairly large steps.”</div> <div><br /></div> <div><strong>What will be the next milestone in the development of quantum computers?</strong></div> <div>“Finding a useful problem that is beyond the reach of ordinary computers, but which a quantum computer with fifty to a hundred qubits can solve. We work intensively on this in collaboration with our industry partners. Probably, it will be within logistics or simulation of large molecules.”</div> <div><br /></div> <div>Text: Ingela Roos</div> <div>Photo: Johan Bodell</div> <div><br /></div> <div>The article has previously been published in Swedish in Chalmers magasin #2 2019</div> <div><br /></div> <div><a href="/en/centres/wacqt">Read more about Wallenberg Centre for Quantum Technology​</a> &gt;&gt;&gt;</div>Wed, 18 Dec 2019 09:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Wieczorek-WAF.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Wieczorek-WAF.aspxQuantum scientist becomes Wallenberg Academy Fellow<p><b><div>Witlef Wieczorek, Assistant Professor at the Quantum Technology Laboratory at MC2, has been honoured with a prestigious Wallenberg Academy Fellow assignment. &quot;It feels just great and I am overwhelmed by this decision and award,&quot; says Witlef.</div></b></p><div><div>The Wallenberg Academy Fellow is a five-year grant which provides young researchers with opportunities to make important scientific breakthroughs by providing long-term research funding in Sweden. Witlef Wieczorek is funded with 7.5 MSEK for the years 2020-2024 with a possibility to apply for five years extension after that.</div> <div>&quot;It feels just great and I am overwhelmed by this decision and award. The Wallenberg Academy Fellow means much to me as it provides me with the opportunity to pursue a long-term and challenging research project, here at Chalmers,&quot; he says.</div> <div><br /></div> <div>Witlef joined MC2 in 2017 as tenure-track Assistant Professor in the Excellence Initiative Nano. Since then, he built up a lab and a research group, whose focus lies on research with mechanical-based quantum devices.</div> <div> </div> <div>As a Wallenberg Academy Fellow, he will pursue his research project entitled &quot;Levitated superconducting mechanical resonators: a novel platform for quantum experiments and sensing&quot;.</div> <div>&quot;The big goal of the project is to prepare a micrometer-sized object in a spatial superposition state. Though superposition states are at the heart of the flourishing field of quantum technologies, such big objects have never been brought into such states.&quot;</div> <div>  </div> <div><img src="/SiteCollectionImages/Institutioner/MC2/News/Witlef%20december2019/witlef_puffbild_portratt_350x305_IMG_8291_adj.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px;width:300px;height:260px" />Witlef gives us an example:</div> <div>&quot;Erwin Schrödinger, one of the founders of quantum mechanics, invented the gedankenexperiment of a cat being dead and alive at the same time. Though, such a state of a cat is in principle allowed by the laws of quantum mechanics, we have never observed superposed cats. The current record in superposition size is held by impressive experiments that observe the interference of large molecules. My project aims to superpose 10 million times heavier objects. This goal is ambitious! Therefore, we construct a novel experimental platform that should make this possible: levitated micrometer-sized superconducting objects that are coupled to superconducting circuitry,&quot; he explains.</div> <div> </div> <div>The Knut and Alice Wallenberg Foundation is announcing 29 new Wallenberg Academy Fellows on 3 December 2019. The underlying intention of this investment is to strengthen Sweden as a research nation by retaining the greatest talent in the country, while also recruiting young international researchers to Sweden.</div> <div>&quot;To make scientific breakthroughs, it is important to concentrate on your research for a long period and have good resources. Wallenberg Academy Fellows provides these conditions, and they are available during what could be the most creative phase of their research careers. They also have the opportunity to participate in a mentoring program, which helps boost their scientific leadership,&quot; says Göran K. Hansson, Secretary General of the Royal Swedish Academy of Sciences.</div> <div><br /></div> <div>Text and photo: Michael Nystås</div> <div><br /></div> <div><div>Read about Witlef Wieczorek's research in brief </div> <div><a href="https://kaw.wallenberg.org/en/witlef-wieczorek" target="_blank"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Can Schrödinger’s cat weigh ten million times as much?​​</a></div> <div><br /></div> <div><div>Read pressrelease from The Knut and Alice Wallenberg Foundation</div> <div><a href="https://kaw.wallenberg.org/en/press/twenty-nine-young-researchers-become-wallenberg-academy-fellows-2019" target="_blank"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Twenty nine young researchers become Wallenberg Academy Fellows 2019​</a></div></div> <div><br /></div> <div><a href="https://kaw.wallenberg.org/en/witlef-wieczorek" target="_blank"></a>Read more about the other two Chalmers researchers who received a research grant through the Wallenberg Adacemy Fellows: </div> <p class="chalmersElement-P"><a href="/en/departments/bio/news/Pages/New-Wallenberg-Academy-Fellow-2019.aspx" target="_blank"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/ichtm.gif" alt="" />Elin Esbjörner - </a><span style="background-color:initial;color:rgb(51, 51, 51)"><a href="/en/departments/bio/news/Pages/New-Wallenberg-Academy-Fellow-2019.aspx" target="_blank">New Wallenberg Academy Fellow seeks to prevent neurodegenerative disorders</a></span></p> <p class="chalmersElement-P"><a href="/en/departments/math/news/Pages/The-mathematics-of-shape-is-addressed-by-new-Wallenberg-Academy-Fellow.aspx" target="_blank"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/ichtm.gif" alt="" />Klas Modin - The mathematics of shape is addressed by new Wallenberg Academy Fellow</a><br /></p></div> <div><br /></div> <div>Read an interview from January 2018 with Witlef Wieczorek</div> <div><a href="/en/departments/mc2/news/Pages/Setting-up-a-new-laboratory-for-mechanical-quantum-device-research.aspx" target="_blank" title="Setting-up-a-new-laboratory-for-mechanical-quantum-device-research"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/ichtm.gif" alt="" />New laboratory for mechanical quantum device research</a></div> <div><br /></div></div>Tue, 03 Dec 2019 10:00:00 +0100https://www.chalmers.se/en/departments/mc2/news/Pages/Lectures-and-discussions-at-quantum-workshop.aspxhttps://www.chalmers.se/en/departments/mc2/news/Pages/Lectures-and-discussions-at-quantum-workshop.aspxLectures and discussions at quantum workshop<p><b>​Some 30 participants from business and academia met at a successful industrial workshop with the Wallenberg Center for Quantum Technology (WACQT) at Chalmers on 23 and 24 May. &quot;This is the fourth time we meet and now we are beginning to find one’s feet. It is fun&quot;, says Göran Johansson, professor of applied quantum physics and one of the main researchers in WACQT.</b></p><div><span style="background-color:initial">On the agenda during the two fully booked days, there were, among other things, presentations of PhD projects from business representatives, and panel discussions that captured the industry's expectations and wishes. Invited speakers from WACQT's scientific advisory board were Steve Girvin, Yale University, USA, Harry Buhrman, QuSoft, the Netherlands, and Charles Marcus, Copenhagen University, Denmark. Giulia Ferrini, assistant professor at MC2, presented the course Advanced Quantum Algorithms, which is a part of WACQT's graduate school for doctoral students.</span><br /></div> <div><br /></div> <div>Since the center was launched on 1 January 2018, a number of industrial partners have been attached to the project. During the workshop representatives from all seven were present in the auditorium Kollektorn, and held their own presentations: Marika Svensson, Jeppesen, Azimeh Sefidcon and Gemma Vall Llosera, Ericsson, Petter Wirfält, Volvo Group, Anders Ström, Saab, Anders Nyqvist, SEB, Mikael Unge, ABB and Anders Broo, Astra Zeneca.</div> <div><br /></div> <div><img src="/SiteCollectionImages/Institutioner/MC2/News/wacqt_wshop_350x305_b.jpg" alt="Picture from workshop." class="chalmersPosition-FloatRight" style="margin:5px" />When we made a visit on Friday we were listening to Jonas Bylander (to the right), associate professor of physics at the Quantum Technology Laboratory, as he spoke about how the project progresses. Also, fellow researchers Laura García Álvarez, Anton Frisk-Kockum, both at the Applied Quantum Physics Laboratory, Stefan Kröll, Lund University, and Gunnar Björk, the Royal Institute of Technology, gave their own lectures on topics such as &quot;Quantum computing and simulation&quot;, &quot;Quantum communication&quot; and &quot;Quantum sensing&quot;. The latter two coordinate the areas of quantum sensors and quantum communication within WACQT.</div> <div><br /></div> <div>The industrial workshop was organized by WACQT coordinator Philip Krantz and Professor Göran Wendin. Linda Brånell was responsible for the logistics and made sure that everything was proceeding smoothly. Professor Wendin was very pleased with the two days:</div> <div>&quot;Personally I am very happy about the result of the workshop. The idea to combine the meeting of the WACQT Strategic Advisory Board (SAB) with a workshop turned out very well. The organisation worked as planned, and the presentations were excellent and at the right level. The discussions during coffee breaks, lunches and dinners were intense. It seems clear that the common industry-academia-PhD projects create strong engagement from both sides, which is very promising for our future efforts&quot;, he says.</div> <div><br /></div> <div>The development of the quantum computer is the main project in the ten-year research program Wallenberg Centre for Quantum Technology, launched at the turn of the year, thanks to a donation of SEK 600 million from the Knut and Alice Wallenberg Foundation. With additional funds from Chalmers, industry and other universities, the total budget is landing nearly SEK 1 billion.</div> <div><br /></div> <div>The goal of the 10-year Wallenberg Center for Quantum Technology research program is to build a functioning quantum computer within ten years. The total investment is almost SEK 1 billion. Most come from the Knut and Alice Wallenberg Foundation, which contributes with 600 million. The rest come from Chalmers, the cooperating universities in Lund, Linköping and the Royal Institute of Technology (KTH), as well as collaborative companies.</div> <div><br /></div> <div>Text and photo: Michael Nystås</div> <div><br /></div> <h3 class="chalmersElement-H3">Read more &gt;&gt;&gt;</h3> <div><a href="/en/news/Pages/Engineering-of-a-Swedish-quantum-computer-set-to-start.aspx">Engineering of a Swedish quantum computer set to start​</a></div> <div><br /></div> <div><a href="/en/departments/mc2/news/Pages/Now-the-quantum-computer-will-become-reality.aspx">Now the quantum computer will become reality</a></div> <div><br /></div> <div><a href="/en/departments/mc2/news/Pages/Well-attended-kickoff-for-new-center-in-quantum-technology.aspx">Well-attended kickoff for new center in quantum technology</a></div> <div><br /></div> <div><h3 class="chalmersElement-H3"><span>Facts about the Wallenberg Center for Quantum Technology</span></h3></div> <div>• Wallenberg Center for Quantum Technology is a ten-year initiative aimed at bringing Swedish research and industry to the front of the second quantum revolution.</div> <div>• The research program will develop and secure Swedish competence in all areas of quantum technology.</div> <div>• The research program includes a focus project aimed at developing a quantum computer, as well as an excellence program covering the four sub-areas.</div> <div>• The Wallenberg Center for Quantum Technology is led by and largely located at Chalmers. The areas of quantum communication and quantum sensors are coordinated by KTH and Lund University.</div> <div>• The program includes a research school, a postdoctoral program, a guest research program and funds for recruiting young researchers. It will ensure long-term Swedish competence supply in quantum technology, even after the end of the program.</div> <div>• Collaboration with several industry partners ensures that applications are relevant to Swedish industry.</div> Tue, 28 May 2019 09:00:00 +0200