TOSHIHIRO NAKAOKA
Dept. Address
7-1 Kioi, Chiyoda-ku, Tokyo 102-8554, Japan.
Personal Details
Name: Toshihiro Nakaoka
Electronic mail:
Work Experience
Professor 4/2017-
Associate Professor 4/2010-3/2017
JST researcher of PRESTO program 10/2008-10/2012
Project Associate Professor 11/2007-3/2010
Project Lecturer 09/2006-10/2007
Guest Scientist 08/2005-04/2006
Walter Schottky Institute, Technical University of Munchen, Germany.
Research Associate 04/2002-08/2006
Researcher 04/2001-03/2002 Institute of Industrial Science, University of Tokyo
Education
Graduate School of Science, Osaka University Osaka, Japan Ph.D. in Physics, Mar. 2001.
Experimental research in nanostructural dynamics of chalcogenide glasses investigated by Raman scattering and photoluminescence measurements under the direction of Prof. Murase. Thesis: "Investigation of nanostructural dynamics and rigidity percolation in network glasses."
Graduate School of Science, Osaka University Osaka, Japan M.A. in Physics, Mar 1999.
Department of Physics, Osaka University Osaka, Japan B.A. in Physics, Mar 1997.
Research
2007-present
- Chalcogenide semiconductors for novel devices and physics:
solid state electrolyte, electrochemical metallization memories (ECM), super-ionic conduction of silver, fractal growth of metal filaments,
photo-induced phenomena, and plasmonics.
- Devices for quantum information technology:
Fabrication and experimental measurement of single photon electron devices using self-assembled dots, nitride nanowires.
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2005-2006
- Time-resolved measurement on quantum mechanically coupled exciton states in a quantum dot molecule (QDM), which is the first observation of PL decay in single QDM. We have also shown
tuning of radiative recombination rate as fraction of direct exciton character is varied.
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2003-2005
- Experimental and theoretical investigation of g-factor of self-assembled quantum dots. Knowledge of electron and hole g-factors, which are the coefficient connecting spin moment with magnetic one, is important to design such spin-based devices. For example, the system with a large g-factor is preferable for controlling spin-qubit while near-zero electron g-factor is suitable to design a quantum receiver. We have investigated the g-factor in self-assembled dots by single dot spectroscopy under applied magnetic field and by 8 band kp calculation. We have demonstrated experimentally and theoretically that the g-factor in InGaAs self-assembled dots can be tuned by changing the dot-size and/or by modifying strain.
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2003-2004
- Time resolved photoluminescence measurement and single dot spectroscopy of vertically-stacked self-assembled quantum dots. We have observed a delay of PL due to non-resonant tunneling between the stacked dots.
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2002-2004
- Fabrication and optical measurement of micromachined airbridge in which quantum dots are embedded. We have controlled the PL emission energy of the dots by using the MEMS device. This type of structure enables deformation coupling between nanomechanical mode of airbridge and a QD.