Witlef Wieczorek, Quantum Technology Laboratory

Abstract: Quantum states of massive objects have fascinated since the inception of quantum mechanics, a famous example being Schrödingers cat. The motion of mechanical resonators weighing picograms to micrograms can nowadays be brought into quantum states. This capability enables tests of the validity of quantum mechanics and provides new avenues within quantum technologies. To explore and utilize the quantum behavior of a massive object requires exceptional isolation from its environment combined with precise control over its quantum state. I will present our experiments that aim at achieving quantum control over the motion of objects with masses larger than 10^12 atomic mass units. These experiments are based on magnetically levitating a superconducting microparticle in cryogenic vacuum at millikelvin temperatures.
Mechanical resonators in various implementations are already in use in many real-world applications, such as for acceleration sensing. Precisely measuring the displacement of a mechanical resonator is also crucial for many scientific endeavors, from the most fundamental discoveries like the detection of gravitational waves to applied research like studies of material surfaces. Light is used in many of these applications to convert the mechanical displacement into a detectable signal. As of today, however, the interaction between light and mechanical motion is weak, limiting the range of applications to the linear interaction regime. I will also present our work towards increasing this interaction to the nonlinear regime based on optomechanical microcavities and novel materials for nanomechanics.