Zeiss Award Recognises Advancements in Quantum Cryptography

Professor Jian-Wei Pan, based at the University of Science and Technology of China, Hefei, was announced as winner of the ZEISS Research Award 2020. One of the world's leading researchers in the field of quantum technology, Jian-Wei Pan is noted for his remarkable work regarding the distribution of entangled photons over a distance of 1,200 km, by far the longest distance ever reached. He achieved this by using a light source installed on a satellite that emits entangled photons.

Entangled photons can be used in conjunction with quantum cryptography to enable two parties to exchange a secret key. According to the laws of quantum mechanics, key exchange security is based on this: every attempt made by an eavesdropper to read the exchanged photons disrupts their quantum state and can be discovered by the communicating parties. If a secret key is exchanged, it can be used for example, to encrypt an email or secure a bank transfer.

In contrast to quantum cryptography, classic key exchange processes are based on the assumption that certain mathematical problems are difficult to solve. If a computer's performance increases faster than anticipated, or a faster algorithm is found to solve these mathematical problems, security can no longer be guaranteed. Professor Pan's research could therefore help to make our communication more tap-proof in the future.

He has also contributed significantly to the development of optical quantum computing. He creates complex quantum states of light, such as ensembles of up to ten entangled photons, or indistinguishable photons from many simultaneously operating single photon sources to perform boson sampling experiments. These experiments lay important foundations for optical quantum computing. The research work shows a way to scale up such systems and thus to make practical use of their advantages.

The biennial ZEISS Research Award, created in 1990, honours outstanding achievements in the field of optics and carries 40,000 euros in prize money. It is normally presented during the ZEISS Symposium, which was due to be held on June 17. In the light of the coronavirus situation this will now be presented to Professor Jian-Wei Pan during the 2021 Symposium.