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Consequences of the local spin self-energy approximation on the heavy Fermion quantum phase transition

Ping Sun·Gabriel Kotliar
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Abstract

We show, using the periodic Anderson model, that the local spin self-energy approximation, as implemented in the extended dynamical mean field theory (EDMFT), results in a first order phase transition which persists to T=0. Around the transition, there is a finite coexistence region of the paramagnetic and antiferromagnetic (AFM) phases. The region is bounded by two critical transition lines which differ by an electron-hole bubble at the AFM ordering wave vector.

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Ping Sun, Gabriel Kotliar. 2005-06-20. Consequences of the local spin self-energy approximation on the heavy Fermion quantum phase transition. https://doi.org/10.1103/physrevb.71.245104

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