Quantum Nano-Scale Magnetics Team

Team Leader

Yoshichika Otani

  • D.Sci.
  • Yoshichika Otani
  • Brief resume
    1989
    D.Sci., Keio University
    1989
    Research Fellow, University of Dublin, Ireland
    1991
    Postdoctoral Researcher, Laboratoire Louis Néel, CNRS, France
    1992
    Research Instructor, Keio University
    1995
    Associate Professor, Tohoku University
    2001
    Team Leader, Quantum Nano-Scale Magnetics Team, RIKEN (-current)
    2004
    Professor, University of Tokyo (-current)

Outline

Quantum Nano-Scale Magnetics Team

Various domain structures such as magnetic vortices and single domains are formed in nano-scale magnets, depending on their shape and size. The magnetic vortices, for example, have two degrees of freedom, i.e., polarity and chirality, and allow us to design an artificial magnetic lattice called “magnonic crystal” consisting of several magnetic vortices. These are expected to be next-generation magnetic memory and logic devices. We fabricate nano-scale magnets to experimentally study their fundamental static and dynamic magnetic properties. We also use nano-scale magnets to produce “pure spin current” which transfers no electric charges but only spin angular momentums. By injecting the pure spin current into non-magnetic metals and superconductors, we are able to observe various interesting phenomena such as the spin Hall effect, the spin injection induced magnetization reversal, and the spin accumulation. We aim to study and develop new types of spintronic devices using the spin injection techniques.

Recent Research Topic

Giant spin accumulation in lateral spin valves with NiFe/MgO/Ag junctions
Fig. 1: Giant spin accumulation in lateral spin valves with NiFe/MgO/Ag junctions
(a) Schematic diagram of spin accumulation measurement by means of nonlocal spin injection. (b) Cross-sectional transmission electron micrograph of a NiFe/MgO/Ag junction. (c) Non-local spin signal as a function of magnetic field.

Selected Publications

  1. Y. Fukuma, et al. Giant enhancement of spin accumulation and long-distance spin precession in metallic lateral spin valves, Nature Mater. 2011, 10, 527.
  2. S. Sugimoto, et al. Dynamics of coupled vortices in a pair of ferromagnetic disks, Phys. Rev. Lett. 2011, 106, 197203.
  3. Y. Niimi, M. Morota, D. H. Wei, C. Deranlot, M. Basletic, A. Hamzic, A. Fert and Y. Otani, Extrinsic spin Hall effect induced by Iridium impurities in Copper, Phys. Rev. Lett. 2011, 106, 126601.
  4. Y. Fukuma, L. Wang, H. Idzuchi and Y. Otani, Enhanced spin accumulation obtained by inserting low-resistance MgO interface in metallic lateral spin valves, Appl. Phys. Lett. 2010, 97, 012507.
  5. A. Barman, T. Kimura, Y. Otani, Y. Fukuma, K. Akahane and S. Meguro, ;Benchtop time-resolved magneto-optical Kerr magnetometer, Rev. Sci. Instrum. 2008, 79, 123905.
  6. T. Yang, T. Kimura and Y. Otani, Giant spin-accumulation signal and pure spin-current-induced reversible magnetization switching, Nature Physics 2008, 4, 851.
  7. L. Vila, T. Kimura and Y. Otani, Evolution of the spin Hall effect in Pt nanowires: Size and temperature effects, Phys. Rev. Lett. 2007, 99, 226604.
  8. T. Kimura, Y. Otani, T. Sato, S. Takahashi and S. Maekawa, Room temperature reversible spin Hall effect, Phys. Rev. Lett. 2007, 98, 156601.

Core Members

Principal Investigator add delete
Yoshichika Otani Team Leader    
Staff Scientist add delete
Postdoctoral Fellow add delete
Student Trainee add delete
Satoshi Sugimoto Junior Research Associate    
Yanping Liu International Program Associate    
Hiroshi Idzuchi Student Trainee    
Technical Assistant add delete
Administrative Assistant add delete
Michiko Ishinabe Assistant    
Visiting Research Staff add delete
Tatsuya Aoki Visiting Scientist    
Yasuhiro Fukuma Visiting Scientist    
Other Staff add delete
Back to Top