|ナノマテリアルテクノロジーセンターCenter for Nano Materials and Technology 2F
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Syoji Yamada Professor
Center for Nano Materials and Technology
Ph.D., Osaka University(1979)
The Solid State Physics Division of NTT Basic Research Labs. in Atsugi,Kanagawa (1986), Associate Professor of School of Materials Science of JAIST (1994-2001), Professor of Nano Materials and Technology of JAIST (2001-)
MBE Growth, Solid State Science, Semiconductor Quantum Transport, Semiconductor Spintronics, Compound Semiconductors Micromachining
Growth of high-quality two-dimensional structures of compond semiconductors
Based on ultra-high vacuum molecular beam epitaxy, we carry out growth of high-quality two-dimensional heterostructures such as modulation doped GaAs/AlGaAs and high-In-content InGaAs/InAlAs, InGaSb/InAlSB heterojunctions and and resonant tunneling structures. Especially in the latter heterojunctions, we confirmed a record low-temperature electron mobility of 5e5cm2/Vsec. Those wafers were used as base materials for fabricating small devices and for studying related mesoscopic as well as spin-related transport physics.
Fabrication of semiconductor base hybrid small structures and their quantum physics including spin transport
Using standard photo- and electron beam (EB) lithographies together with focused ion beam (FIB) and scanning tunneling microscopy (STM) fabrication techniques, we make small structure devices such as wires and dots, and small hybrid devices especially with ferromagnetic metals. In those samples, we study mainly transport physics such as conductance fluctuation / quantization, Coulomb blockades, spin-related phenomena for realization of quantum functional and/or spin-controlled devices. Quantum computation devices are the future target of those researches.
Analysis of band structures in low-dimensional electron systems
By utilizing conventional magnetic field-related methods such as magneto-resistance, magneto-tunneling, far-infrared cyclotron resonance etc, we are analyzing accurate subband structures of confined low-dimensional systems (electrons and holes). If necessary, we use ultra-high magnetic field facilities in other Universities and Institutions.
Micromechanic parts (cantilever) by using semiconductor micro fabrication technologies
We study batch fabrication technologies for producing ceramic / semicondcutor hybrid macro (nano)-machines with some companies. Our mission is to fabricate small semiconductor opto- and electronic-devices and / or mechanical parts which could be coupled with large mechanical parts made mechanically from various ceramics. This hybrid micro (nano)-machines could serve a new class intelligent and customized devices in electronics, mechanics, chemistry and biology.
Developement of ultra-precise cantilever sensor/probe by utilizing srain-driven semiconductor lithography process
By applying the strain-driven lithography process to the semiconductor multilayers having several strained layers, ultra-precise cantilever sensors/probes such as ultra-small or highly flexible cantilevers and highly uniform cantilever arrays are developing toward the applications in future scanning probe microscopy and probe cards for LSI testers.
Novel quantum transport properties observed in bi-layer two-dimensional electron gas system having strong Rashba spin-orbit coupling
By fabricating narrow-gap heterostructures, which has two-layer two-dimensional electron gas (2DEG) with strong Rashba type spin-orbit coupling, we explore the new aspect of transport properties related to the interaction between the 2DEG systems.
- Magnetic field dependency of spin-splittingin In0.75Ga0.25As/ In0.75Al0.25As two dimensional electron gas with strong Rashba spin-orbit coupling，Syoji Yamada, Shunsaku Nitta, Hiuma Iwase, Masashi Akabori, Yasutaka Imanaka and Tadashi Takamasu，Journal of Physics: Conference Series 012063，334，2011，October 2011
- Cyclotron resonance of two dimensional Rashba systems in InGaAs，Yasutaka Imanaka, Tadashi Takamasu, Shunsaku Nitta and Syoji Yamada，Journal of Physics: Conference Series 012061，334，2011，October 2011
- Selective area molecular beam epitaxy of InAs on GaAs (110) masked substrates for direct fabrication of planar nanowire field-effect transistors，M. Akabori, T. Murakami and S. Yamada，J. Crystal Growth，Vol. 345，pp. 22-26，2012
◇Lectures and Presentations
- Low temperature anisotropic transport and related structure analysis in InGaAs two-dimensional electron gas bilayer system，M. Akabori, W. Wei, S. Hidaka, H. Iwase, S. Yamada,H. Hirayama and Y. Suzuki，Int. Conf. on Molecular Beam Epitaxy 2012，Nara, Japan，September 23-28, 2012
- Verification of electrical spin injection into InGaAs two-dimensional electron gas from CoFe electrode by four-terminal non-local geometry，Shiro Hidaka, Taro Kondo, M. Akabori, and S. Yamada，31st Int. Conf. on Physics of Semiconductors，Zurich, Switzerland，July 22-27, 2012
- Control of In0.75Ga0.25As 2DEG bilayer systemfor new type Rashba spintronics devices，M. Akabori, H. Nakano, S. Hidaka, H. Iwase, and S. Yamada，31st Int. Conf. on Physics of Semiconductors，Zurich, Switzerland，July 22-28, 2012
◇Academic Society Affiliations
- Japan Physical Society，2010-2011
- Physical Socciety of Japan，2005-2007
- JAIST Nanotechnology 2008, International Sympojium on Novel Nano-Electro-Mechanical 3D Structures: Fabrication and Properties，Co-chair，2008/10/23 - 2008/10/25
- Member of Physical Society of Japan, Society of Applied Physics and American Institute of Physics
- Guest Reseacher in Blackett Laboratories, Imperial College (1992)
■Academic Awards Received
- Award for the Scientific Research of "Basic Approach toward Quantum Information Processign Devices"，Shibuya Support Foundation for Science, Culture and Sports
- JJAP Editorial Contribution Award，The Japan Society of Applied Physics