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Density dependence of microwave induced magneto-resistance oscillations in a two-dimensional electron gas

B. Simovic·C. Ellenberger·K. Ensslin·Wegscheider
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Abstract

We have measured the magneto-resistance of a two-dimensional electron gas (2DEG) under continuous microwave irradiation as a function of electron density and mobility tuned with a metallic top-gate. In the entire range of density and mobility we have investigated, we observe microwave induced oscillations of large amplitude that are B-periodic. These B-periodic oscillations are reminiscent of the ones reported by Kukushkin \textit{et al}[1] and which were attributed to the presence of edge-magneto-plasmons. We have found that the B-periodicity does not increase linearly with the density in our sample but shows a plateau in the range (2.4-3) 10^{11}\rm cm^{-2} $. In this regime, the phase of the B-periodic oscillations is found to shift continuously by two periods.

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B. Simovic, C. Ellenberger, K. Ensslin, Wegscheider. 2005-02-15. Density dependence of microwave induced magneto-resistance oscillations in a two-dimensional electron gas. https://doi.org/10.1103/physrevb.71.233303

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