124 citations · 312 across the 17 of their papers we have counts for
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Time-resolved measurement of ambipolar edge magnetoplasmon transport in InAs/InGaSb composite quantum wells
Hiroshi Kamata, Hiroshi Irie, Norio Kumada +1
Time-resolved charge transport measurement for one-dimensional edge states is a powerful means for investigating nonequilibrium charge dynamics and underlying interaction effects t…
Energy gap tuning and gate-controlled topological phase transition in InAs/InGaSb composite quantum wells
H. Irie, T. Akiho, F. Couëdo +3
We report transport measurements of strained InAs/InGaSb composite quantum wells (CQWs) in the quantum spin Hall phase, focusing on the control of the energy gap thro…
Determination of -factor in InAs two-dimensional electron system by capacitance spectroscopy
Hiroshi Irie, Takafumi Akiho, Koji Muraki
We determine the effective -factor () of a two-dimensional electron gas (2DEG) using a new method based on capacitance spectroscopy. The capacitance-voltage profile of…
Impact of epitaxial strain on the topological-nontopological phase diagram and semimetallic behavior of InAs/GaSb composite quantum wells
H. Irie, T. Akiho, F. Couëdo +4
We study the influence of epitaxial strain on the electronic properties of InAs/GaSb composite quantum wells (CQWs), host structures for quantum spin Hall insulators, by transport…
Counterflowing edge current and its equilibration in quantum Hall devices with sharp edge potential: Roles of incompressible strips and contact configuration
T. Akiho, H. Irie, K. Onomitsu +1
We report the observation of counterflowing edge current in InAs quantum wells which leads to the breakdown of quantum Hall (QH) effects at high magnetic fields. Counterflowing edg…
Pseudospin Berry phase as a signature of nontrivial band topology in a two-dimensional system
F. Couëdo, H. Irie, T. Akiho +3
Electron motion in crystals is governed by the coupling between crystal momentum and internal degrees of freedom such as spin implicit in the band structure. The description of thi…
Engineering quantum spin Hall insulators by strained-layer heterostructures
Takafumi Akiho, François Couëdo, Hiroshi Irie +3
Quantum spin Hall insulators (QSHIs), also known as two-dimensional topological insulators, have emerged as an unconventional class of quantum states with insulating bulk and condu…
Single-edge transport in an InAs/GaSb quantum spin Hall insulator
François Couëdo, Hiroshi Irie, Kyoichi Suzuki +2
We report transport measurements in a single edge channel of an InAs/GaSb quantum spin Hall insulator, where the conduction occurs through only one pair of counterpropagating edge…
Evaluation of Disorder Introduced by Electrolyte Gating through Transport Measurements in Graphene
Andrew Browning, Norio Kumada, Yoshiaki Sekine +3
We evaluate the degree of disorder in electrolyte gating devices through the transport measurements in graphene. By comparing the mobility in ion- and standard metal-gated devices,…
Andreev reflection and bound state formation in a ballistic two-dimensional electron gas probed by a quantum point contact
Hiroshi Irie, Clemens Todt, Norio Kumada +4
We study coherent transport and bound-state formation of Bogoliubov quasiparticles in a high-mobility InGaAs two-dimensional electron gas (2DEG) coupled to a sup…
Josephson coupling through one-dimensional ballistic channel in semiconductor-superconductor hybrid quantum point contacts
Hiroshi Irie, Yuichi Harada, Hiroki Sugiyama +1
We study a superconducting quantum point contact made of a narrow InGaAs channel with Nb proximity electrodes. The narrow channel is formed in a gate-fitted con…