Hideaki Takayanagi

Hideaki Takayanagi
Takayanagi Laboratory, Department of Applied Physics, Tokyo University of Science
Mesoscopic Superconductivity and Quantum Information Physics
Academic degree:
Ph.D. (science) The University of Tokyo, 1987
Recent Publications
See NIMS Researchers DB
Home Page:
Takayanagi Laboratory, Tokyo University of Science (in Japanese)

Education & Working History

2006 Professor, Department of Applied Physics, Tokyo University of Science
2003 Guest Professor at the Royal Institute of Technology (Stockholm)
2003 - 2006 Guest Professor at the University of Tokyo
2003 - 2006 Concurrent Professor at Nanjing University (China)
2003 Director, NTT Basic Research Laboratories
1997 Guest Professor at Chalmers University of Technology (Sweden)
1996 Guest Professor at Delft University of Technology (The Netherlands)
1991 Research Group Leader, NTT Basic Research Laboratories
1988 Guest Researcher in the department of physics at UC Berkeley (one year)
1977 Joined Musashino Electrical Communication Laboratory, NTT
1977 B.S. from the University of Tokyo, Dept. of Basic Sciences

Research History

Mesoscopic superconductivity is a novel research field, whose purpose is to analyze superconducting quantum effect in mesoscopic region. Hideaki Takayanagi marked the beginning in its research by detecting superconducting proximity effect in a junction of Nb -InAs - Nb. This was considered one of the most important findings because it provided answer to a long-debated controversial issue on existence of superconducting current under pure two-dimensional system, and it documented ability of gate potential to control maximum value of supercurrent. Control of supercurrent had eventually led to development of Josephson field effect transistor (JOFET) by him. He predicted that supercurrent of superconducting quantum point contact can be quantized and succeeded in establishing his own theory by forming split gate using the semiconductor heterostructure developed by himself. He also has been working on spintronics field using this heterostructure. He and his colleagues showed that spin-orbit interaction in the quantum well can be controlled by gate voltage. This result is considered as a milestone in this field.

In these years, he has been engaged in superconducting quantum computation research using micrometersized superconducting quantum interference device (SQUID) as quantum bit. He has observed multiphoton Rabi oscillation with different frequency microwave photons. Moreover he had successful result in measuring vacuum Rabi oscillation in flux quantum bit coupled with a LC-resonator for the first time. It not only is a significant technology for fruition of quantum computer but also made it possible to directly control quantum macroscopic system. He is gradually building up a leading role in quantum computation research. Takayanagi's work field range drastically, however, in basics he has been involved in the research of superconducting quantum effect in mesoscopic field. Such world's first-ever achievements were highly evaluated internationally and he was invited to Nobel Symposium in Sweden three times.

Selected Papers

  1. Quantum time-evolution in qubit readout process with a Josephson bifurcation amplifier
    Nakano H, Saito S, Semba K, Takayanagi H
    Phys Rev Lett, 2009; 102(25): 257003.
  2. Luminescence of a Cooper pair
    Asano Y, Suemune I, Takayanagi H, Hanamura E
    Phys Rev Lett, 2009; 103(18): 187001.
  3. Two-photon probe of the Jaynes-Cummings model and controlled symmetry breaking in circuit QED
    Deppe F, Mariantoni M, Menzel EP, Marx A, Saito S, Kakuyanagi K, Tanaka H, Meno T, Semba K, Takayanagi H, Solano E, Gross R
    Nature Physics, 2008; 4: 686-691.
  4. Vacuum Rabi oscillations in a macroscopic superconducting qubit LC oscillator system
    Johannson J, Saito S, Meno T, Nakano H, Ueda M, Semba K, Takayanagi H
    Phys Rev Lett, 2006; 96(12): 127006.
  5. Ferromagnetism in semiconductor dot array
    Tamura H, Shiraishi K, Takayanagi H
    Jpn J Appl Phys, 2000; 39: L241.
  6. Gate control of spin-orbit interaction in an inverted In0.53Ga0.47As/In0.52Al0.48As Heterostructure
    Nitta J, Akazaki T, Takayanag H, Enoki T
    Phys Rev Lett, 1997; 78(7): 1335-1338.
  7. AC long-range phase-coherent effects in mesoscopic superconductor—normal metal structures
    Volkov AF, Takayanagi H
    Phys Rev Lett, 1996; 76, 4026.
  8. Observation of maximum supercurrent quantization in a superconducting quantum point contact
    Takayanagi H, Akazaki T, Nitta J
    Phys Rev Lett, 1995; 75(19): 3533-3536.
  9. Mesoscopic fluctuations of the critical current in a superconductor—normal-conductor—superconductor
    Takayanagi H, Hansen JB, Nitta J
    Phys Rev Lett, 1995; 74(1): 166-169.
  10. Superconducting proximity effect in the native inversion layer on InAs
    Takayanagi H, Kawakami T
    Phys Rev Lett, 1985; 54(22): 2449-2452.