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arXiv · 1604.06449

Critical local moment fluctuations and enhanced pairing correlations in a cluster Anderson model

Ang Cai·J. H. Pixley·Kevin Ingersent·Qimiao Si
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Abstract

The appearance of unconventional superconductivity near heavy-fermion quantum critical points (QCPs) motivates investigation of pairing correlations close to a ``beyond Landau'' Kondo-destruction QCP. We focus on a two-Anderson-impurity cluster in which Kondo destruction is induced by a pseudogap in the conduction-electron density of states. Analysis via continuous-time quantum Monte-Carlo and the numerical renormalization group reveals a previously unstudied QCP that both displays the critical-local moment fluctuations characteristic of Kondo destruction and leads to a strongly enhanced singlet-pairing susceptibility. Our results provide new insights into the mechanism for superconductivity in quantum critical metals.

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Ang Cai, J. H. Pixley, Kevin Ingersent, Qimiao Si. 2016-04-21. Critical local moment fluctuations and enhanced pairing correlations in a cluster Anderson model. https://doi.org/10.1103/physrevb.101.014452

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