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arXiv · 1412.1371

The photoresponse of a two-dimensional electron gas at the second harmonic of the cyclotron resonance

M. Białek·M. Czapkiewicz·J. Wróbel·V. Umansky·J. Łusakowski
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Abstract

Terahertz spectroscopy experiments at magnetic fields and low temperatures were carried out on samples of different gate shapes processed on a high electron mobility GaAs/AlGaAs heterostructure. For a given radiation frequency, multiple magnetoplasmon resonances were observed with a dispersion relation described within a local approximation of the magnetoconductivity tensor. The second harmonic of the cyclotron resonance was observed and its appearance was interpreted as resulting from a high frequency, inhomogeneous electromagnetic field on the border of a two-dimensional electron gas with a metallic gate and/or an ohmic contact.

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M. Białek, M. Czapkiewicz, J. Wróbel, V. Umansky, J. Łusakowski. 2014-12-03. The photoresponse of a two-dimensional electron gas at the second harmonic of the cyclotron resonance. https://doi.org/10.1103/physrevb.91.045437

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