was chosen by the editors of the Physical Review Letters as one of their "milestone letters", i.e. papers that made important contributions to physics, announced significant discoveries, or started new areas of research. His subsequent work with John Rarity and Paul Tapster, from the Defence Research Agency (DRA) in Malvern, resulted in the proof-of-principle experimental quantum key distribution, introducing parametric down-conversion, phase encoding and quantum interferometry into the repertoire of cryptography. He and collaborators were the first to develop the concept of a security proof based on entanglement purification. Ekert and colleagues have made a number of contributions to both theoretical aspects of quantum computation and proposals for its experimental realisations. These include proving that almost any quantum logic gate operating on two quantum bits is universal, proposing one of the first realistic implementations of quantum computation, e.g. using the induced dipole-dipole coupling in an optically driven array of quantum dots, introducing more stable geometric quantum logic gates, and proposing "noiseless encoding", which became later known as decoherence free subspaces. His other notable contributions include work on quantum state swapping, optimal quantum state estimation and quantum state transfer. With some of the same collaborators, he has written on connections between the notion of mathematical proofs and the laws of physics. He has also contributed semi-popular writing on the history of science. Honours and awards For his discovery of quantum cryptography he was awarded the 1995 Maxwell Medal and Prize by the Institute of Physics, the 2007 Hughes Medal by the Royal Society and the 2019 Micius Quantum Prize. He is also a co-recipient of the 2004 European Union Descartes Prize. In 2016 he was elected a Fellow of the Royal Society. He is a fellow of the Singapore National Academy of Science and a recipient of the 2017 Singapore Public Administration Medal (Silver) Pingat Pentadbiran Awam. He is a foreign member of the Polish Academy of Arts and Sciences. See also List of Poles References External links "Cryptoreality (Part I): From Ancient Ciphers to Quantum Computers – A Conversation with Artur Ekert", Ideas Roadshow, 2017 "Cryptoreality (Part II): Applied Foundational Physics – A Conversation with Artur Ekert", Ideas Roadshow, 2017 1961 births Living people Scientists from Wrocław Jagiellonian University alumni Alumni of Wolfson College, Oxford Quantum physicists 21st-century Polish physicists 21st-century British physicists Academic staff of the National University of Singapore Fellows of Merton College, Oxford Maxwell Medal and Prize