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Angle-dependent magnetotransport in GaAs/InAs core/shell nanowires.

ABSTRACT: We study the impact of the direction of magnetic flux on the electron motion in GaAs/InAs core/shell nanowires. At small tilt angles, when the magnetic field is aligned nearly parallel to the nanowire axis, we observe Aharonov-Bohm type h/e flux periodic magnetoconductance oscillations. These are attributed to transport via angular momentum states, formed by electron waves within the InAs shell. With increasing tilt of the nanowire in the magnetic field, the flux periodic magnetoconductance oscillations disappear. Universal conductance fluctuations are observed for all tilt angles, however with increasing amplitudes for large tilt angles. We record this evolution of the electron propagation from a circling motion around the core to a diffusive transport through scattering loops and give explanations for the observed different transport regimes separated by the magnetic field orientation.

SUBMITTER: Haas F

PROVIDER: S-EPMC4835758 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Angle-dependent magnetotransport in GaAs/InAs core/shell nanowires.

Haas Fabian F Wenz Tobias T Zellekens Patrick P Demarina Nataliya N Rieger Torsten T Lepsa Mihail M Grützmacher Detlev D Lüth Hans H Schäpers Thomas T

Scientific reports 20160419

We study the impact of the direction of magnetic flux on the electron motion in GaAs/InAs core/shell nanowires. At small tilt angles, when the magnetic field is aligned nearly parallel to the nanowire axis, we observe Aharonov-Bohm type h/e flux periodic magnetoconductance oscillations. These are attributed to transport via angular momentum states, formed by electron waves within the InAs shell. With increasing tilt of the nanowire in the magnetic field, the flux periodic magnetoconductance osci ...[more]

PMID: 27091000

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