RIKEN Center for Emergent Matter Science Quantum Effect Device Research Team

Team Leader: Koji Ishibashi (D.Eng.)

Japanese Page

Research Summary

To explore future nanoelectronics, we develop fabrication processes of sub-10 nm structures, and study their electroical and optical properties to apply them to functional nanodevices. We use carbon nanotubes, semiconductor (Ge/Si, InAs, InSb et al.) nanowires, graphene and functional molecules as building blocks of those nanostructures. Besides, we are interested in organic optical devices combined with plasmonic structures . With a combination of the top-down and bottom-up technologies, we fabricate quantum dots, CNT/molecule heterostructures and semiconductor/superconductor hybrid nanostructures for use in single electron devices and quantum computing devices.

Main Research Fields

Complex Systems

Related Research Fields

Mathematical & Physical Sciences
Engineering

Keywords

Quantum devices
Nanostructures
Nanofabrication

Selected Publications

1. Michael D. Randle, Masayuki Hosoda, Russell S. Deacon, Manabu Ohtomo, Patrick Zellekens, Kenji Watanabe, Takashi Taniguchi, Shota Okazaki, Takao Sasagawa, Kenichi Kawaguchi, Shintaro Sato, Koji Ishibashi,
"Gate-defined Josephson Weak-Links in Monolayer WTe₂"
Advanced Materials, 35, 2301683 (2023)
2. Patrick Zellekens, Russell Deacon, Pujitha Perla, Detlev Grutzmacher, Mihail Lepsa, Thomas Schapers, and Koji Ishibashi,
"Microwave spectroscopy of Andreev states in InAs nanowire-based hybrid junctions using a flip-chip layout"
Communications Physics, 5, 267 (2022)
3. Akira Hida and Koji Ishibashi,
"Exciton Controlled-NOT Gate Using Coupled Quantum Dots in Carbon Nanotube",
ACS Photonics, 9, 3398 (2022)
4. Joseph Hillier, Keiji Ono, Kouta Ibukuro, Fayong Liu, Zuo Li, Muhammad Husain, Harvey Rutt, Isao Tomita, Yoshishige Tsuchiya, Koji Ishibashi, Shinichi Saito,
"Probing hole spin transport of disorder quantum dots via Pauli spin-blockade in standard silicon transistors",
Nanotechnology, 32 260001 (2021)
5. Patrick Zellekens, Russell Deacon, Pujitha Perla, H. Aruni Fonseka, Timm Morstedt, Steven A. Hindmarsh, Benjamin Bennemann, Florian Lentz, Mihail I. Lepsa, Ana M. Sanchez, Detlev Grutzmacher, Koji Ishibashi, and Thomas Schapers,
"Hard-Gap Spectroscopy in a Self-Defined Mesoscopic InAs/Al Nanowire Josephson Junction",
Phys. Rev. Applied 14, 054019 (2020)
6. Rui Wang, Russell S. Deacon, Jian Sun, Jun Yao, Charles M. Lieber, Koji Ishibashi,
"Gate Tunable Hole Charge Qubit Formed in a Ge/Si Nanowire Double Quantum Dot Coupled to Microwave Photons",
Nano Lett. 19, 1052 (2019)
7. Jian Sun, Russell Deacon, Rui Wang, Jun Yao, Charles M. Lieber, Koji Ishibashi,
"Helical Hole State in Multiple Conduction Modes in Ge/Si Core/Shell Nanowire",
Nano Lett. 18, 6144-6149 (2018)
8. Russell Deacon, Jonas Wiedenmann, Erwann Bocquillon, Teun M. Klapwijk, Philipp Leubner, Christoph Brune, Seigo Tarucha, Koji Ishibashi, Hartmut Buhmann, Laurens W. Molenkamp,
"Josephson radiation from gapless Andreev bound states in HgTe-based topological junctions",
Phys. Rev. X 7, 021011 (2017)
9. Erwann Bocquillon, Russell Deacon, Jonas Wiedenmann, Philipp Leubner, Teun M. Klapwijk, Christoph Brune, Koji Ishibashi, H. Buhmann, Laurens W. Molenkamp,
"Gapless Andreev bound states in the quantum spin Hall insulator HgTe",
Nature Nanotechnology, 12, 137 (2017)
10. J. Wiedenmann, E. Bocquillon, R.S. Deacon, S. Hartinger, O. Herrmann, T.M. Klapwijk, L. Maier, C. Ames, C. Bru¨ne, C. Gould, A. Oiwa, K. Ishibashi, S. Tarucha, H. Buhmann & L.W. Molenkamp,
"4Π-periodic Josephson supercurrent in HgTe-based topological Josephson junctions",
Nature Commun. 7, 10303 (2016)

Recent Research Results

Jul. 1, 2015
Producing spin-entangled electrons

Lab Members

Principal investigator

Koji Ishibashi: Team Leader

Core members

Keiji Ono: Senior Research Scientist
Russell Stewart Deacon: Senior Research Scientist
Hui Wang: Postdoctoral Researcher

Contact Information

W407, Cooperation Center, 2-1 Hirosawa, Wako, Saitama
351-0198 Japan
Email: kishiba [at] riken.jp