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Exchange energy and generalized polarization in the presence of spin-orbit coupling in two dimensions

S. Chesi·G. F. Giuliani
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Abstract

We discuss a general form of the exchange energy for a homogeneous system of interacting electrons in two spatial dimensions which is particularly suited in the presence of a generic spin-orbit interaction. The theory is best formulated in terms of a generalized fractional electronic polarization. Remarkably we find that a net generalized polarization does not necessarily translate into an increase in the magnitude of the exchange energy, a fact that in turn favors unpolarized states. Our results account qualitatively for the findings of recent experimental investigations.

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S. Chesi, G. F. Giuliani. 2007-02-06. Exchange energy and generalized polarization in the presence of spin-orbit coupling in two dimensions. https://doi.org/10.1103/physrevb.75.155305

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