What is Quantum Technology?

Quantum physics, from theory to ongoing revolution

In the early 1900s observations were made that were not consistent with traditional, classical physics. For example, researchers concluded that hot, black bodies emitted electromagnetic radiation at wavelengths that were not expected, and that atoms could only emit and absorb light of specific frequencies.
In 1900 the physicist Max Planck suggested that light was emitted in small, discrete “packages” – that it was quantised – in order to explain these discrepancies. This marked the start of quantum physics, which describes the world at the atomic level. The brightest physicists of the time, including Niels Bohr and Albert Einstein, led further development. They soon realised that they were on the trail of a paradigm shift, rather than just an adjustment to classical physics. In the 1930s, quantum theory was essentially complete, even though many of its consequences were only understood much later.
Quantum physics has had an enormous impact on society. By exploiting the characteristics of quantum physics in light and materials researchers invented both the laser and the transistor. Such inventions form the basis of information technology as a whole – computers, the internet and much more besides – which to a large extent shape today’s society. This was the first quantum revolution.
But even though researchers learnt how to exploit certain quantum characteristics, it was long regarded as impossible to control individual quantum systems such as individual atoms, electrons or light particles (photons). It was only in the 1980s that researchers succeeded in developing methods for measuring and controlling individual atoms and photons, work resulting in the award of the 2012 Nobel Prize in Physics. In parallel with this, other researchers developed electronic components from semi-conductors and superconductors, in which they could manipulate individual electrons. 
The control of individual quantum systems has opened the door to a second quantum revolution, offering entirely new possibilities. Today there are goals such as extremely rapid computers, intercept-proof communications and hyper-sensitive measuring methods.
After many years of fundamental research the applications are coming within reach, and researchers as well as policy-makers and business managers are starting to realise that quantum technology has the potential to change our society significantly. Significant investment is now going into quantum technology throughout the world. The EU is launching a decade-long billion-euro investment programme in 2019. There are programmes that are at least as extensive in North America, Asia and Australia. IT companies such as Google, IBM, Intel and Microsoft are also making significant investments in quantum technology.

Published: Mon 27 Nov 2017.