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arXiv · 1712.01667

Dynamic correlations in the highly dilute 2D electron liquid: loss function, critical wave vector and analytic plasmon dispersion

Jürgen T. Drachta·Dominik Kreil·Raphael Hobbiger·Helga M. Böhm
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Abstract

Correlations, highly important in low--dimensional systems, are known to decrease the plasmon dispersion of two-dimensional electron liquids. Here we calculate the plasmon properties, applying the 'Dynamic Many-Body Theory', accounting for correlated two-particle--two-hole fluctuations. These dynamic correlations are found to significantly lower the plasmon's energy. For the data obtained numerically, we provide an analytic expression that is valid across a wide range both of densities and of wave vectors. Finally, we demonstrate how this can be invoked in determining the actual electron densities from measurements on an AlGaAs quantum well.

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Jürgen T. Drachta, Dominik Kreil, Raphael Hobbiger, Helga M. Böhm. 2017-12-05. Dynamic correlations in the highly dilute 2D electron liquid: loss function, critical wave vector and analytic plasmon dispersion. https://doi.org/10.1016/j.physe.2017.09.020

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