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arXiv · 1403.3956

Roton-maxon spectrum and instability for weakly interacting dipolar excitons in a semiconductor layer

A. K. Fedorov·I. L. Kurbakov·Yu. E. Lozovik
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Abstract

The formation of the roton-maxon excitation spectrum and the roton instability effect for a weakly correlated Bose gas of dipolar excitons in a semiconductor layer are predicted. The stability diagram is calculated. According to our numerical estimations, the threshold of the roton instability for Bose-Einstein condensed exciton gas with roton-maxon spectrum is achievable experimentally, e.g., in GaAs semiconductor layers.

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A. K. Fedorov, I. L. Kurbakov, Yu. E. Lozovik. 2014-03-16. Roton-maxon spectrum and instability for weakly interacting dipolar excitons in a semiconductor layer. https://doi.org/10.1103/physrevb.90.165430

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