Quantum electron transport and terahertz dynamics in deep nm-scale structures

  • 2.1 Quantum bits, memories, devices(Superconducting circuits, Ion trapping, Trapped cold atoms, Photons, Quantum dots, etc.)
  • 2.2 Quantum sensing(Quantum metrology/Sensing/Imaging, Optical lattice clocks)
  • 2.3 Quantum materials(Topological materials/Thermoelectric devices/Functional materials)
Kazuhiko Hirakawa
Institute for Nano Quantum Information Electronics
Director, Professor
Nanoscience Center for Photonics, Electronics, and Materials Engineering, Institute of Industrial Science  Professor
It is becoming increasingly important to conduct research to open up new horizons in electronics by forming transistors that use extremely small systems such as quantum dots and single molecules as the active layer, and using their electron dynamics.
We have clarified the conduction characteristics of an extremely small quantum nanostructures by using ultrafine metal electrodes with an atomic-scale gap, and focus the terahertz electromagnetic wave on the nanostructure far beyond the diffraction limit.
In addition to elucidating electronic states and conduction dynamics, we are conducting research to control and apply them and promote a new field called "terahertz nanoscience".
(left) Single molecule transistor (SMT) (right) terahertz spectroscopy of single molecules by using the SMT geometry
S. Du, K. Yoshida, Y. Zhang, I. Hamada, and K. Hirakawa, Nature Photonics, vol.12, pp. 608-612, (2018).
Fast and sensitive terahertz bolometer using a doubly clamped MEMS beam resonator
Y. Zhang, Y. Watanabe, S. Hosono, Nagai, and K. Hirakawa, Applied Physics Letters, vol. 108, pp. 163503-1~4 (2016).

Related links

Research collaborators

  • The University of Tokyo
  • Tohoku University
  • Osaka University
  • Kyoto University
  • NICT
  • Ecole Normale Superieure

Related publications

  • S. Du, K. Yoshida, Y. Zhang, I. Hamada, and K. Hirakawa: “Terahertz dynamics of electron–vibron coupling in single molecules with tunable electrostatic potential”, Nature Photonics, vol.12, pp. 608-612, (2018)
  • Y. Zhang, Y. Watanabe, S. Hosono, Nagai, and K. Hirakawa: “Room temperature, very sensitive thermometer using a doubly clamped microelectromechanical beam resonator for bolometer applications”, Applied Physics Letters, vol. 108, pp. 163503-1~4 (2016)
  • K. Yoshida, K. Shibata, and K. Hirakawa: “Terahertz field enhancement and photon-assisted tunneling in single-molecule transistors”, Physical Review Letters, vol. 115, pp. 138302-1~5 (2015)
  • Y. Zhang, K. Shibata, N. Nagai, C. Ndebeka-Bandou, G. Bastard, and K. Hirakawa: “Terahertz intersublevel transitions in single self-assembled InAs quantum dots with variable electron numbers”, Nano Letters, vol. 15, pp. 1166~1170 (2015)


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