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Thomas-Fermi-Dirac-von Weizsacker hydrodynamics in laterally modulated electronic systems

B. P. van Zyl·E. Zaremba
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Abstract

We have studied the collective plasma excitations of a two-dimensional electron gas with an arbitrary lateral charge-density modulation. The dynamics is formulated using a previously developed hydrodynamic theory based on the Thomas-Fermi-Dirac-von Weizsacker approximation. In this approach, both the equilibrium and dynamical properties of the periodically modulated electron gas are treated in a consistent fashion. We pay particular attention to the evolution of the collective excitations as the system undergoes the transition from the ideal two-dimensional limit to the highly-localized one-dimensional limit. We also calculate the power absorption in the long-wavelength limit to illustrate the effect of the modulation on the modes probed by far-infrared (FIR) transmission spectroscopy.

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B. P. van Zyl, E. Zaremba. 1998-08-06. Thomas-Fermi-Dirac-von Weizsacker hydrodynamics in laterally modulated electronic systems. https://doi.org/10.1103/physrevb.59.2079

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