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arXiv · 1405.1090

Colossal negative magnetoresistance in a 2D electron gas

Q. Shi·P. D. Martin·Q. A. Ebner·M. A. Zudov·L. N. Pfeiffer·K. W. West
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Abstract

We report on a colossal negative magnetoresistance (MR) in GaAs/AlGaAs quantum well which, at low temperatures, is manifested by a drop of the resistivity by more than an order of magnitude at a magnetic field $B \approx 1$ kG. In contrast to MR effects discussed earlier, the MR reported here is not parabolic, even at small $B$, and persists to much higher in-plane magnetic fields and temperatures. Remarkably, the temperature dependence of the resistivity at $B \approx 1$ kG is linear over the entire temperature range studied (from 1 to 30 K) and appears to coincide with the high-temperature limit of the zero-field resistivity, hinting on the important role of acoustic phonons.

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Q. Shi, P. D. Martin, Q. A. Ebner, M. A. Zudov, L. N. Pfeiffer, K. W. West. 2014-05-05. Colossal negative magnetoresistance in a 2D electron gas. https://doi.org/10.1103/physrevb.89.201301

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