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arXiv · 1003.5920

Colossal magnetoresistance in an ultra-clean weakly interacting 2D Fermi liquid

Xiaoqing Zhou·B. A. Piot·M. Bonin·L. W. Engel·S. Das Sarma·G. Gervais·L. N. Pfeiffer·K. W. West
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Abstract

We report the observation of a new phenomenon of colossal magnetoresistance in a 40 nm wide GaAs quantum well in the presence of an external magnetic field applied parallel to the high-mobility 2D electron layer. In a strong magnetic field, the magnetoresistance is observed to increase by a factor of ~300 from 0 to 45T without the system undergoing any metal-insulator transition. We discuss how this colossal magnetoresistance effect cannot be attributed to the spin degree-of-freedom or localization physics, but most likely emanates from strong magneto-orbital coupling between the two-dimensional electron gas and the magnetic field. Our observation is consistent with a field-induced 2D-to-3D transition in the confined electronic system.

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Xiaoqing Zhou, B. A. Piot, M. Bonin, L. W. Engel, S. Das Sarma, G. Gervais, L. N. Pfeiffer, K. W. West. 2010-03-30. Colossal magnetoresistance in an ultra-clean weakly interacting 2D Fermi liquid. https://doi.org/10.1103/physrevlett.104.216801

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