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arXiv · 1408.1775

Strongly anisotropic ballistic magnetoresistance in compact three-dimensional semiconducting nanoarchitectures

Ching-Hao Chang·Jeroen van den Brink·Carmine Ortix
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Abstract

We establish theoretically that in nonmagnetic semiconducting bilayer or multilayer thin film systems rolled up into compact quasi-one-dimensional nanoarchitectures, the ballistic magnetoresistance is very anisotropic: conductances depend strongly on the direction of an externally applied magnetic field. This phenomenon originates from the curved open geometry of rolled-up nanotubes, which leads to a tunability of the number of quasi-one-dimensional magnetic subbands crossing the Fermi energy. The experimental significance of this phenomenon is illustrated by a sizable anisotropy that scales with the inverse of the winding number, and persists up to a critical temperature that can be strongly enhanced by increasing the strength of the external magnetic field or the characteristic radius of curvature, and can reach room temperature.

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Ching-Hao Chang, Jeroen van den Brink, Carmine Ortix. 2014-12-03. Strongly anisotropic ballistic magnetoresistance in compact three-dimensional semiconducting nanoarchitectures. https://doi.org/10.1103/physrevlett.113.227205

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