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arXiv · 1611.04521

Simple embedding scheme for the spectral properties of the Single-Impurity Anderson Model

Soumyodipto Mukherjee·David R. Reichman
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Abstract

In this work we outline a simple and numerically inexpensive approach to describe the spectral features of the single-impurity Anderson model. The method combines aspects of the density matrix embedding theory (DMET) approach with a spectral broadening approach inspired by those used in numerical renormalization group (NRG) methods. At zero temperature for a wide range of U , the spectral function produced by this approach is found to be in good agreement with general expectations as well as more advanced and complex numerical methods such as DMRG-based schemes. The theory developed here is simply transferable to more complex impurity problems.

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Soumyodipto Mukherjee, David R. Reichman. 2017-04-07. Simple embedding scheme for the spectral properties of the Single-Impurity Anderson Model. https://doi.org/10.1103/physrevb.95.155111

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