Search Results - "KUMADA, Norio"

Ultrafast intrinsic optical-to-electrical conversion dynamics in a graphene photodetector by Yoshioka, Katsumasa, Wakamura, Taro, Hashisaka, Masayuki, Watanabe, Kenji, Taniguchi, Takashi, Kumada, Norio

“…Optical-to-electrical conversion in graphene is a central phenomenon for realizing anticipated ultrafast and low-power-consumption information technologies…”
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On-chip coherent frequency-domain THz spectroscopy for electrical transport by Yoshioka, Katsumasa, Kumada, Norio, Muraki, Koji, Hashisaka, Masayuki

“…We developed a coherent frequency-domain terahertz (THz) spectroscopic technique on a coplanar waveguide in the ultrabroad frequency range from 200 MHz to 1.6…”
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Fast time-domain current measurement for quantum dot charge sensing using a homemade cryogenic transimpedance amplifier by Bohuslavskyi, Heorhii, Hashisaka, Masayuki, Shimizu, Takase, Akiho, Takafumi, Muraki, Koji, Kumada, Norio

“…We developed a high-speed and low-noise time-domain current measurement scheme using a homemade GaAs high-electron-mobility-transistor-based cryogenic…”
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Effects of GaAs buffer layer on quantum anomalous Hall insulator Vy(BixSb1−x)2−yTe3 by Nakazawa, Yusuke, Akiho, Takafumi, Kanisawa, Kiyoshi, Irie, Hiroshi, Kumada, Norio, Muraki, Koji

“…We report the growth, structural characterization, and transport properties of the quantum anomalous Hall insulator Vy(BixSb1−x)2−yTe3 (VBST) grown on a GaAs…”
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Coherent-Incoherent Crossover of Charge and Neutral Mode Transport as Evidence for the Disorder-Dominated Fractional Edge Phase by Hashisaka, Masayuki, Ito, Takuya, Akiho, Takafumi, Sasaki, Satoshi, Kumada, Norio, Shibata, Naokazu, Muraki, Koji

“…Couplings between topological edge channels open electronic phases possessing nontrivial eigenmodes far beyond the noninteracting-edge picture. However,…”
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Dynamical d-wave condensation of exciton–polaritons in a two-dimensional square-lattice potential by Kim, Na Young, Kusudo, Kenichiro, Wu, Congjun, Masumoto, Naoyuki, Löffler, Andreas, Höfling, Sven, Kumada, Norio, Worschech, Lukas, Forchel, Alfred, Yamamoto, Yoshihisa

“…Similar to atoms in cold gases, exciton–polaritons in semiconductor microcavities can undergo Bose–Einstein condensation. Now, formation of a condensate in an…”
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Active spatial control of terahertz plasmons in graphene by Tu, Ngoc Han, Yoshioka, Katsumasa, Sasaki, Satoshi, Takamura, Makoto, Muraki, Koji, Kumada, Norio

“…Graphene offers the possibility for actively controlling plasmon confinement and propagation by tailoring its spatial conductivity. However, implementation of…”
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Coupling between quantum Hall edge channels on opposite sides of a Hall bar by Tu, Ngoc Han, Hashisaka, Masayuki, Ota, Takeshi, Sekine, Yoshiaki, Muraki, Koji, Fujisawa, Toshimasa, Kumada, Norio

“…We investigate the coupling between quantum Hall (QH) edge channels (ECs) located at opposite sides of a 50-μm-wide Hall bar by exciting a charged wavepacket…”
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Low-Frequency Spin Dynamics in a Canted Antiferromagnet by Kumada, Norio, Muraki, Koji, Hirayama, Yoshiro

“…Resistively detected nuclear spin relaxation measurements in closely separated two-dimensional electron systems reveal strong low-frequency electron-spin…”
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Low-frequency spin fluctuations in Skyrmions confined by wires: measurements of local nuclear spin relaxation by Kobayashi, Takashi, Kumada, Norio, Ota, Takeshi, Sasaki, Satoshi, Hirayama, Yoshiro

“…We investigate low-frequency electron spin dynamics in a quantum Hall system with wire confinement by nuclear spin relaxation measurements. We developed a…”
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GaAs microcavity exciton-polaritons in a trap by Kim, Na Young, Lai, Chih-Wei, Utsunomiya, Shoko, Roumpos, Georgios, Fraser, Michael, Deng, Hui, Byrnes, Tim, Recher, Patrik, Kumada, Norio, Fujisawa, Toshimasa, Yamamoto, Yoshihisa

“…We present a simple method to create an in‐plane lateral potential in a semiconductor microcavity using a metal thin‐film. Two types of potential are produced:…”
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Terahertz electronics generate and detect graphene plasmon polaritons

“…Graphene plasmon polaritons are expected to enable rapid data transfer and processing; however, these plasmons are difficult to access. Terahertz electronics…”
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NMR study of a canted antiferromagnet in a bilayer quantum Hall system by Kumada, Norio, Muraki, Koji, Hirayama, Yoshiro

“…We investigate static and dynamic properties of electron spins in the bilayer quantum Hall system at total Landau level filling factor ν = 2 by using…”
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Effects of screening on the propagation of graphene surface plasmons by Sasaki, Ken-ichi, Kumada, Norio

“…Electromagnetic fields bound tightly to charge carriers in a two-dimensional sheet, namely surface plasmons, are shielded by metallic plates that are a part of…”
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n + -GaAs Back-Gated Double-Quantum-Well Structures with Full Density Control by Koji Muraki, Koji Muraki, Norio Kumada, Norio Kumada, Tadashi Saku, Tadashi Saku, Yoshiro Hirayama, Yoshiro Hirayama

“…We present the fabrication of a novel double-quantum-well (DQW) structure, in which the upper electron layer is supplied via modulation doping while the lower…”
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Effects of inversion asymmetry on electron-nuclear spin coupling in semiconductor heterostructures : Possible role of spin-orbit interactions by HASHIMOTO, Katsushi, MURAKI, Koji, KUMACA, Norio, SAKU, Tadashi, HIRAYAMA, Yoshiro

“…We show that electron-nuclear spin coupling in semiconductor heterostructures is strongly modified by their potential inversion asymmetry. This is demonstrated…”
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Andreev Reflection in the Quantum Hall Regime at an Al/InAs Junction on a Cleaved Edge by Akiho, Takafumi, Irie, Hiroshi, Nakazawa, Yusuke, Sasaki, Satoshi, Kumada, Norio, Muraki, Koji

“…We have fabricated a superconductor/semiconductor junction composed of Al and InAs using cleaved edge overgrowth. By exploiting the unique geometry with a thin…”
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Coherence Time of Nuclear Spins in GaAs Quantum Well Probed by Submicron-Scale All-Electrical Nuclear Magnetic Resonance Device by Ota, Takeshi, Kumada, Norio, Yusa, Go, Miyashita, Sen, Fujisawa, Toshimasa, Hirayama, Yoshiro

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Plasmon Control Driven by Spatial Carrier Density Modulation in Graphene by Takamura, Makoto, Kumada, Norio, Wang, Shengnan, Kumakura, Kazuhide, Taniyasu, Yoshitaka

“…Self-assembled monolayers of organosilane formed at the interfaces between graphene and SiO2/Si substrates were used for selective-area modulation of the…”
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Resonant edge magnetoplasmons and their decay in graphene by Kumada, N, Roulleau, P, Roche, B, Hashisaka, M, Hibino, H, Petković, I, Glattli, D C

“…We investigate resonant edge magnetoplasmons (EMPs) and their decay in graphene by high-frequency electronic measurements. From EMP resonances in disk shaped…”
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