Yoshihisa Yamamoto

Yoshihisa Yamamoto is currently the Director of Physics & Informatics (PHI) Laboratories at NTT Research, Inc., in Sunnyvale, California. He is also Professor Emeritus in the Departments of Electrical Engineering and Applied Physics at Stanford University, and Professor Emeritus at the National Institute of Informatics, Tokyo. He received his BS from the Institute of Science Tokyo, and his MS and PhD from the University of Tokyo.

He pioneered the research of coherent optical communications and optical amplifier repeaters in the late 1970s and early 1980s. In the late 1980s, he demonstrated squeezed-state generation in constant-current-driven semiconductor lasers and quantum non-demolition (QND) measurements using optical-fiber soliton collisions. Later, his research focus shifted to semiconductor cavity quantum electrodynamics and quantum transport in mesoscopic systems. He developed microcavity quantum dots for indistinguishable single-photon generation, spin–photon entanglement, and violation of Bell’s inequality. Another major contribution during this period was the prediction and experimental demonstration of exciton–polariton condensation and superfluidity in semiconductor microcavities.

Yamamoto pioneered the research of a special-purpose optical computer, known as coherent Ising machines (CIM), designed to solve NP-hard Ising problems and related combinatorial optimization problems. The CIM concept was subsequently extended to coherent SAT solvers and coherent XY machines.

He is a Fellow of Optica, APS, and JSAP. His honors include the Charles Hard Townes Medal, the Achievement Award of the Institute of Electronics, Information and Communication Engineers of Japan, the Nishina Prize, the Carl Zeiss Award, the IEEE PS Quantum Electronics Award, the Matsuo Science Prize, the Medal of Honor with Purple Ribbon from the Government of Japan, the Hermann Anton Haus Lecturer at MIT, the Okawa Prize, and the Willis E. Lamb Award.