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Scientist

Leonard Mandel

1927–2001 · quantum optics, physics
British-American physicist, one of the pioneers of quantum optics. He is best known as a co-discoverer of the Hong–Ou–Mandel effect, which demonstrates two-photon interference and the indistinguishability of quantum particles. His experiments and theoretical work laid the foundation for quantum information and quantum computing. He made significant contributions to statistical optics and the study of non-classical light.

Biography

Leonard Mandel was born on 9 May 1927 in Berlin, Germany. Due to his Jewish background, his family emigrated to England and then to the USA. He earned his doctorate at the University of London. He worked at Imperial College London and then at the University of Rochester, where he spent most of his career. Together with Chun Ki Hong and Zheyu Ou in 1987, he experimentally observed the effect of two-photon interference. He was awarded the Max Born Award and other honors. He died on 9 February 2001.

Key discoveries

💡 Mandel became interested in optics after attending a lecture by Dennis Gabor, the inventor of holography, which determined his future scientific path.
Concepts
quantum opticsquantum entanglementquantum informationquantum measurement
Laws
Hong–Ou–Mandel effect
Scientists
Charles TownesAlain AspectErwin SchrödingerDavid DeutschShuji NakamuraJohn Stewart BellNiels BohrAlbert A. Michelson

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