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Evaluation of the optical conductivity tensor in terms of contour integrations

Laszlo Szunyogh·Peter Weinberger
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Abstract

For the case of finite life-time broadening the standard Kubo-formula for the optical conductivity tensor is rederived in terms of Green's functions by using contour integrations, whereby finite temperatures are accounted for by using the Fermi-Dirac distribution function. For zero life-time broadening, the present formalism is related to expressions well-known in the literature. Numerical aspects of how to calculate the corresponding contour integrals are also outlined.

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Laszlo Szunyogh, Peter Weinberger. 2000-12-11. Evaluation of the optical conductivity tensor in terms of contour integrations. https://doi.org/10.1088/0953-8984%2F11%2F50%2F333

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