Yasunobu Nakamura

A physicist at NEC and later the University of Tokyo and RIKEN.

In 1999 Nakamura, Yuri Pashkin and Jaw-Shen Tsai created and controlled a superposition of two charge states in a tiny superconducting circuit, the 'Cooper-pair box'. It was the first time a coherent quantum state had been engineered in a chip made with ordinary electronics fabrication. It lasted only nanoseconds, but it worked.

It showed that qubits could be built, lithographed and wired like integrated circuits, which opened the path that IBM, Google, Rigetti and many others now follow. Superconducting qubits operate in nanoseconds and are easy to link on a chip, but they must be cooled close to absolute zero.