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arXiv · cond-mat/0701726

Magnetoresistance Oscillations in Two-dimensional Electron Systems Induced by AC and DC Fields

Abstract

We report on magnetotransport measurements in a high-mobility two-dimentional electron system subject simultaneously to AC (microwave) and DC (Hall) fields. We find that DC excitation affects microwave photoresistance in a nontrivial way. Photoresistance maxima (minima) evolve into minima (maxima) and back, reflecting strong coupling and interplay of AC- and DC-induced effects. Most of our observations can be explained in terms of indirect electron transitions using a new, ``combined'' resonant condition. Observed quenching of microwave-induced zero resistance by a DC field cannot be unambiguously linked to a domain model, at least until a systematic theory treating both excitation types within a single framework is developed.

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W. Zhang, M. A. Zudov, L. N. Pfeiffer, K. W. West. 2007-01-29. Magnetoresistance Oscillations in Two-dimensional Electron Systems Induced by AC and DC Fields. https://doi.org/10.1103/physrevlett.98.106804

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