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arXiv · 1807.11343

Reversal of particle-hole scattering-rate asymmetry in Anderson impurity model

R. Zitko·H. R. Krishnamurthy·B. Sriram Shastry
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Abstract

We study the particle-hole asymmetry of the scattering rate in strongly correlated electron systems by examining the cubic $\omega^3$ and $\omega T^2$ terms in the imaginary part of the self-energy of the Anderson impurity model. We show that the sign is opposite in the weak-coupling and strong-coupling limits, explaining the differences found in theoretical approaches taking the respective limits as the starting points. The sign change in fact precisely delineates the cross-over between the weak and strong correlation regimes of the model. For weak interaction $U$ the sign reversal occurs for small values of the doping $\delta=1-n$, while for interaction of order $U \approx 2 \Gamma$, $\Gamma$ being the hybridization strength, the cross-over curve rapidly shifts to the large-doping range. This curve based on the impurity dynamics is genuinely different from other cross-over curves defined through impurity thermodynamic and static properties.

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R. Zitko, H. R. Krishnamurthy, B. Sriram Shastry. 2018-07-30. Reversal of particle-hole scattering-rate asymmetry in Anderson impurity model. https://doi.org/10.1103/physrevb.98.161121

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