Yasunobu Nakamura (中村 泰信 Nakamura Yasunobu) is a Japanese physicist. He is a professor at the University of Tokyo's Research Center for Advanced Science and Technology (RCAST)^[6] and the Principal Investigator of the Superconducting Quantum Electronics Research Group (SQERG) at the Center for Emergent Matter Science (CEMS) within RIKEN.^[7] He has contributed primarily to the area of quantum information science,^[8] particularly in superconducting quantum computing and hybrid quantum systems.^[9][10][11]

While a child, Nakamura's family moved from Osaka to Hinode, Tokyo, where he would gain his early education.^[12] He obtained his Bachelor of Science (1990), Master of Science (1992), and Ph.D. (2011) degrees at the University of Tokyo. In 1999, as a researcher at NEC, Nakamura and collaborators Yuri Pashkin and Jaw-Shen Tsai demonstrated "electrical coherent control of a qubit in a solid-state electronic device"^[4] and in 2001 "realized the first measurement of the Rabi oscillations associated with the transition between two Josephson levels in the Cooper pair box"^[13][14] in a configuration developed by Michel Devoret and colleagues in 1998.^[13][15]

In 2000, Nakamura was featured as a "Younger Scientist" by the Japan Society of Applied Physics for his work at NEC in "quantum-state control of nanoscale superconducting devices."^[16] From 2001-2002, he visited the group of Hans Mooij [de] at TU Delft on a sabbatical from NEC, where he worked with Irinel Chiorescu, Kees Harmans, and Mooij to create the first flux qubit.^[17][18][19] In 2003, he was named one of MIT Technology Review's top innovators under 35 years old, in which editors noted that "Nakamura and a collaborator got two qubits to interact in a manner that had been predicted but never demonstrated" at the time.^[20]

As of 3 October 2016^[update], the Japan Science and Technology Agency (科学技術振興機構) announced funding for Nakamura's work through their Exploratory Research for Advanced Technology (ERATO) program.^[21] The project, entitled Macroscopic Quantum Machines,^[22] seeks to dramatically improve quantum state control technology to further the field of quantum computing. Of principal focus is the development of a highly scalable platform for implementing quantum information processing techniques, as well as the creation of hybrid quantum systems which interface with microwave quantum optics. In an article in Nikkei Science [ja] in 2018, it was announced that work towards the construction of a quantum computer with 100 superconducting qubits was underway.^[23] In 2019, the Japanese Ministry of Education, Culture, Sports, Science and Technology launched a quantum technology project known as QLEAP, with Nakamura as the team leader for the quantum information processing component.^[24] The project aims to develop superconducting quantum computers and other quantum technologies over a ten-year period, by increasing collaboration between academia and industry.

In past years, Nakamura and collaborators have published their findings on the efficient detection of single microwave frequency photons,^[25] the suppression of quasiparticles in superconducting quantum computing environments for the improvement of qubit coherence times,^[26] the development of "a deterministic scheme to generate maximal entanglement between remote superconducting atoms, using a propagating microwave photon as a flying qubit",^[27] and the realization of a hybrid quantum system by the strong, coherent coupling between a collective magnetic mode of a ferromagnetic sphere and a superconducting qubit.^[2]

More recently, results have been published in which superconducting qubits were used to resolve quanta of magnon number states,^[28][29] to create a quantitatively non-classical photon number distribution,^[30] to measure fluctuations in a surface acoustic wave (SAW) resonator,^[31] and to measure an itinerant microwave photon in a quantum nondemolition (QND) detection experiment.^[32][33] A superconducting circuit was later used to realize information-to-work conversion by a Maxwell's demon,^[34] radio waves and optical light were optomechanically coupled to surface acoustic waves,^[35] and an ordered vortex lattice in a Josephson junction array was observed.^[36]

Nakamura has spoken several times at quantum information science conferences and seminars, including at the University of Vienna,^[37] the Institute for Theoretical Atomic Molecular and Optical Physics at Harvard University,^[38][39] the National Center of Competence in Research's Quantum Science and Technology Monte Verità conference,^[40] the Institute for Quantum Computing at the University of Waterloo,^[41] the Institute for Molecular Engineering at the University of Chicago^[42] the Institute for Quantum Optics and Quantum Information (IQOQI),^[43] and the Yale Quantum Institute at Yale University.^[44]

In 2020, Nakamura was named as a fellow of the American Physical Society for "the first demonstration of coherent time-dependent manipulation of superconducting qubits, and for contributions to the development of superconducting quantum circuits, microwave quantum optics, and hybrid quantum systems".^[45]

• 1999 – Young Investigator Award, Japan Society of Applied Physics^[46]
• 1999 – The 1st Sir Martin Wood Prize for Japan^[47][48]
• 1999 – The 45th Nishina Memorial Prize^[49]
• 2003 – TR100, MIT Technology Review^[20]
• 2004 – Agilent Technologies Europhysics Prize (with Michel Devoret, Daniel Esteve, and Hans Mooij)^[50]
• 2008 – Simon Memorial Prize (with Jaw-Shen Tsai)^[51]
• 2014 – The 11th Leo Esaki Prize [ja] (with Jaw-Shen Tsai)^[52]
• 2018 - The 19th JSAP Outstanding Achievement Award^[53][54]
• 2020 - American Physical Society (APS) Fellow^[45]