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Anisotropic magnetoresistance in a 2DEG in a quasi-random magnetic field

A. W. Rushforth·B. L. Gallagher·P. C. Main·A. C. Neumann·M. Henini·C. H. Marrows·B. J. Hickey
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Abstract

We present magnetotransport results for a 2D electron gas (2DEG) subject to the quasi-random magnetic field produced by randomly positioned sub-micron Co dots deposited onto the surface of a GaAs/AlGaAs heterostructure. We observe strong local and non-local anisotropic magnetoresistance for external magnetic fields in the plane of the 2DEG. Monte-Carlo calculations confirm that this is due to the changing topology of the quasi-random magnetic field in which electrons are guided predominantly along contours of zero magnetic field.

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A. W. Rushforth, B. L. Gallagher, P. C. Main, A. C. Neumann, M. Henini, C. H. Marrows, B. J. Hickey. 2003-08-22. Anisotropic magnetoresistance in a 2DEG in a quasi-random magnetic field. https://doi.org/10.1103/physrevb.70.193313

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