FLEX-description of the spectral functions near singlet-triplet transition

Bertalan Horváth

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arXiv · 1006.4287

FLEX-description of the spectral functions near singlet-triplet transition

Bertalan Horváth

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Abstract

In a previous article, we have investigated the non-equilibrium two-level Anderson model with a simple iterative perturbation theory. Here we use here a more sophisticated perturbative method, the fluctuation-exchange (FLEX) approximation. The great advantage of FLEX is its \textit{conserving} nature, and that it can describe well the Kondo energy scale, the Kondo-temperature, $T_{K}$. As it was expected from the results obtained with iterative perturbation theory, the FLEX description can give back also the relevant features of the spectral properties.

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Bertalan Horváth. 2010-06-22. FLEX-description of the spectral functions near singlet-triplet transition. https://arxiv.org/abs/1006.4287

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