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Rigorous Schrieffer-Wolff transformation for the Anderson impurity model

Gilles Poirot
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Abstract

With the help of computer algebra, I devise an exact unitary transformation for the Anderson impurity model which allows to kill the hybridization term in the slightly simplified case of zero chemical potential. Then I compute explicitly the outcome of this transformation. This is a rigorous version of the well known Schrieffer-Wolff transformation. It should be possible to treat the general case at the price of increased computation time.

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Gilles Poirot. 2000-04-01. Rigorous Schrieffer-Wolff transformation for the Anderson impurity model. https://arxiv.org/abs/cond-mat/0004005

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