249 citations · 569 across the 20 of their papers we have counts for
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In-plane magnetic field dependence of cyclotron relaxation time in a Si two-dimensional electron system
Tasuku Chiba, Ryuichi Masutomi, Kentarou Sawano +2
Cyclotron resonance of two-dimensional electrons is studied for a high-mobility Si/SiGe quantum well in the presence of an in-plane magnetic field, which induces spin polarization.…
Metallic Behavior of Cyclotron Relaxation Time in Two-Dimensional Systems
Ryuichi Masutomi, Kohei Sasaki, Ippei Yasuda +4
Cyclotron resonance of two-dimensional electrons is studied at low temperatures down to 0.4 K for a high-mobility Si/SiGe quantum well which exhibits a metallic temperature depende…
Well-width dependence of valley splitting in Si/SiGe quantum wells
Kohei Sasaki, Ryuichi Masutomi, Kiyohiko Toyama +3
The valley splitting in Si two-dimensional electron systems is studied using Si/SiGe single quantum wells (QWs) with different well widths. The energy gaps for 4 and 5.3 nm QWs, ob…
Insulating Phases Induced by Crossing of Partially Filled Landau Levels in a Si Quantum Well
Tohru Okamoto, Kohei Sasaki, Kiyohiko Toyama +3
We study magnetotransport in a high mobility Si two-dimensional electron system by in situ tilting of the sample relative to the magnetic field. A pronounced dip in the longitudina…
Evidence for Two-Dimensional Spin-Glass Ordering in Submonolayer Fe Films on Cleaved InAs Surfaces
Toshimitsu Mochizuki, Ryuichi Masutomi, Tohru Okamoto
Magnetotransport measurements have been performed on two-dimensional electron gases formed at InAs(110) surfaces covered with a submonolayer of Fe. Hysteresis in the magnetoresista…
Alkali-metal-induced Fermi level and two dimensional electrons at cleaved InAs(110) surfaces
Masaaki Minowa, Ryuichi Masutomi, Toshimitsu Mochizuki +1
Low-temperature Hall measurements have been performed on two-dimensional electron gases (2DEGs) induced by deposition of Cs or Na on in situ cleaved surfaces of p-type InAs. The su…
Electronic Transport Properties of the Ising Quantum Hall Ferromagnet in a Si Quantum Well
Kiyohiko Toyama, Takahisa Nishioka, Kentarou Sawano +2
Magnetotransport properties are investigated for a high mobility Si two dimensional electron systems in the vicinity of a Landau level crossing point. At low temperatures, the resi…
Quantum Hall effect at cleaved InSb surfaces and low-temperature annealing effect
Ryuichi Masutomi, Masayuki Hio, Toshimitsu Mochizuki +1
We have performed low-temperature in-plane magnetotransport measurements on two-dimensional electron systems induced by deposition of Ag at {\it in situ} cleaved surfaces of {\it p…
Ettingshausen Effect around Landau Level Filling Factor nu=3 Studied by Dynamic Nuclear Polarization
Yosuke Komori, Satoru Sakuma, Tohru Okamoto
Spin current perpendicular to the electric current is investigated around Landau level filling factor in a GaAs/AlGaAs two-dimensional electron system. Measurements of dynami…
Dynamic nuclear polarization induced by hot electrons
Yosuke Komori, Tohru Okamoto
A new method for local dynamic nuclear polarization is demonstrated in a GaAs/AlGaAs heterostructure at the Landau level filling factor . Using a narrow channel sample, where…
Electrically detected electron spin resonance in a high mobility silicon quantum well
Junya Matsunami, Mitsuaki Ooya, Tohru Okamoto
The resistivity change due to electron spin resonance (ESR) absorption is investigated in a high-mobility two-dimensional electron system formed in a Si/SiGe heterostructure. Resul…
Two-dimensional electrons at a cleaved semiconductor surface: Observation of the quantum Hall effect
Yukihide Tsuji, Toshimitsu Mochizuki, Tohru Okamoto
Low-temperature in-plane magnetotransport measurements have been performed on adsorbate-induced electron systems formed at in-situ cleaved surfaces of p-type InAs. The Ag-coverage…
Observation of the Ettingshausen effect in quantum Hall systems
Yosuke Komori, Tohru Okamoto
Evidence of the Ettingshausen effect in the breakdown regime of the integer quantum Hall effect has been observed in a GaAs/AlGaAs two-dimensional electron system. Resistance of mi…
Spin polarization and metallic behavior of a silicon two-dimensional electron system
Tohru Okamoto, Mitsuaki Ooya, Kunio Hosoya +1
We have studied the magnetic and transport properties of an ultra-low-resistivity two-dimensional electron system in a Si/SiGe quantum well. The spin polarization increases linearl…