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arXiv · 0807.0153

Photo-current and photo-voltage oscillations in the two-dimensional electron system: screening and "anti-screening" of a potential profile

S. I. Dorozhkin·I. V. Pechenezhskiy·L. N. Pfeiffer·K. W. West·V. Umansky·K. von Klitzing·J. H. Smet
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Abstract

We observe in state-of-the-art GaAs based 2D electron systems microwave induced photo-current and photo-voltage oscillations around zero as a function of the applied magnetic field. The photo-signals pass zero whenever the microwave frequency is close to a multiple of the cyclotron resonance frequency. They originate from built-in electric fields due to for instance band bending at contacts. The oscillations correspond to a suppression (screening) or an enhancement ("anti-screening") of these fields by the photo-excited electrons.

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S. I. Dorozhkin, I. V. Pechenezhskiy, L. N. Pfeiffer, K. W. West, V. Umansky, K. von Klitzing, J. H. Smet. 2008-07-01. Photo-current and photo-voltage oscillations in the two-dimensional electron system: screening and "anti-screening" of a potential profile. https://doi.org/10.1103/physrevlett.102.036602

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