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Related papers: A Gate-Defined Quantum Point Contact in an InAs Tw…

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We consider spin-resolved cyclotron trajectories in a magnetic focusing device with quantum point source and drain contacts defined within the InSb two-dimensional electron gas and their mapping by the scanning gate microscopy. Besides the…

Mesoscale and Nanoscale Physics · Physics 2018-10-17 Alina Mrenca-Kolasinska , Krzysztof Kolasinski , Bartłomiej Szafran

The appearance and evolution of an anomalous conductance plateau at 0.4 (in units of 2e2/h) in an In0.52Al0.48As/InAs quantum point contact (QPC), in the presence of lateral spin-orbit coupling, has been studied at T=4.2K as a function of…

Mesoscale and Nanoscale Physics · Physics 2011-07-14 P. P. Das , K. B. Chetry , N. Bhandari , J. Wan , M. Cahay , R. S. Newrock , S. T. Herbert

We study the transport properties of the two-dimensional electron gas in AlGaAs/GaAs heterostructures in parallel to the interface magnetic fields at low temperatures. The magnetoresistance in the metallic phase is found to be positive and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. S. Khrapai , E. V. Deviatov , A. A. Shashkin , V. T. Dolgopolov

The conductance change due to a local perturbation in a phase-coherent nanostructure is calculated. The general expressions to first and second order in the perturbation are applied to the scanning gate microscopy of a two-dimensional…

Mesoscale and Nanoscale Physics · Physics 2010-10-13 Rodolfo A. Jalabert , Wojciech Szewc , Steven Tomsovic , Dietmar Weinmann

We report the observation of an anomalous conductance plateau near G = 0.5 G0 (G0 = 2e2/h) in asymmetrically biased AlGaAs/GaAs quantum point contacts (QPCs), with in-plane side gates in the presence of lateral spin-orbit coupling. This is…

Mesoscale and Nanoscale Physics · Physics 2012-04-24 N. Bhandari , P. P. Das , M. Cahay , R. S. Newrock , S. T. Herbert

We report on spatially resolved measurements of the spin-orbit effective magnetic field in a GaAs/InGaAs quantum-well. Biased gate electrodes lead to an electric-field distribution in which the quantum-well electrons move according to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 L. Meier , G. Salis , E. Gini , I. Shorubalko , K. Ensslin

A yet unexplored area in graphene electronics is the field of quantum ballistic transport through graphene nanostructures. Recent developments in the preparation of high mobility graphene are expected to lead to the experimental…

The magnetoresistance of a low carrier density, disordered GaAs based two-dimensional (2D) electron gas has been measured in parallel magnetic fields up to 32 T. The feature in the resistance associated with the complete spin polarization…

Mesoscale and Nanoscale Physics · Physics 2009-11-09 B. A. Piot , D. K. Maude , U. Gennser , A. Cavanna , D. Mailly

Strong spin-orbit coupling, the resulting large $g$ factor, and small effective mass make InAs an attractive material platform for inducing topological superconductivity. The surface Fermi level pinning in the conduction band enables highly…

Introduction of a Josephson field effect transistor (JoFET) concept sparked active research on proximity effects in semiconductors. Induced superconductivity and electrostatic control of critical current has been demonstrated in…

Mesoscale and Nanoscale Physics · Physics 2019-06-26 Zhong Wan , Aleksandr Kazakov , Michael J. Manfra , Loren N. Pfeiffer , Ken W. West , Leonid P. Rokhinson

We study particle and spin transport in a single mode quantum point contact using a charge neutral, quantum degenerate Fermi gas with tunable, attractive interactions. This yields the spin and particle conductance of the point contact as a…

We present measurements of quantized conductance in electrostatically induced quantum point contacts in bilayer graphene. The application of a perpendicular magnetic field leads to an intricate pattern of lifted and restored degeneracies…

The thermodynamic potential of an ideal nonrelativistic gas of two-dimensional electrons in crossed uniform magnetic and electric fields is constructed. For low temperatures and very weak electric fields, it is shown that the Hall…

Condensed Matter · Physics 2007-05-23 Choon-Lin Ho , V. R. Khalilov , Chi Yang

We have used gated GaAs/AlGaAs heterostructures to explore nonlinear transport between spin-resolved Landau level (LL) edge states over a submicron region of two-dimensional electron gas (2DEG). The current I flowing from one edge state to…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 David C. Dixon , Keith R. Wald , Paul L. McEuen , M. R. Melloch

Transport in a two-dimensional electron gas subject to an external magnetic field is analyzed in the presence of a \textit{longitudinal barrier.} We show that \textit{quantum interference of the edge states} bound by the longitudinal…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 A. M. Kadigrobov , M. V. Fistul , K. B. Efetov

We realize a device, based on InAs two-dimensional electron gas proximitized by superconducting Al, which allows a single quantum dot level to be used as a spectrometer of the density of states in a nanowire. Applying a magnetic field…

Topological superconductivity can be engineered in semiconductors with strong spin-orbit interaction coupled to a superconductor. Experimental advances in this field have often been triggered by the development of new hybrid material…

Usually the conductivity is quantized as the inverse of the resistivity, \rho=hc/ie^2, \sigma=ie^2/hc and the velocity versus the electric field is linear, v=\mu E where \mu is the mobility of the electrons.However,when the applied electric…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Keshav N. Shrivastava

The conductance quantization and shot noise below the first conductance plateau $G_0 = 2e^2/h$ are measured in a quantum point contact fabricated in a GaAs/AlGaAs tunnel-coupled double quantum well. From the conductance measurement, we…

Mesoscale and Nanoscale Physics · Physics 2020-03-25 D. Terasawa , S. Norimoto , T. Arakawa , M. Ferrier , A. Fukuda , K. Kobayashi , Y. Hirayama

We consider determination of spin-orbit (SO) coupling constants for the two-dimensional electron gas from measurements of electric properties in rotated in-plane magnetic field. %Due to the interplay Due to the SO coupling the electron…

Mesoscale and Nanoscale Physics · Physics 2016-10-05 K. Kolasiński , H. Sellier , B. Szafran