A simple variational method for calculating energy and quantum capacitance of an electron gas with screened interactions

Brian Skinner; M. M. Fogler

doi:10.1103/physrevb.82.201306

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arXiv · 1009.5430

A simple variational method for calculating energy and quantum capacitance of an electron gas with screened interactions

Brian Skinner·M. M. Fogler

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Abstract

We describe a variational procedure for calculating the energy of an electron gas in which the long-range Coulomb interaction is truncated by the screening effect of a nearby metallic gate. We use this procedure to compute the quantum capacitance of the system as a function of electron density and spin polarization. The accuracy of the method is verified against published Monte-Carlo data. The results compare favorably with a recent experiment.

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Brian Skinner, M. M. Fogler. 2010-09-28. A simple variational method for calculating energy and quantum capacitance of an electron gas with screened interactions. https://doi.org/10.1103/physrevb.82.201306

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