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arXiv · 1308.0839

Pairing Correlations Near a Kondo-Destruction Quantum Critical Point

J. H. Pixley·Lili Deng·Kevin Ingersent·Qimiao Si
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Abstract

Motivated by the unconventional superconductivity observed in heavy-fermion metals, we investigate pairing susceptibilities near a continuous quantum phase transition of the Kondo-destruction type. We solve two-impurity Bose-Fermi Anderson models with Ising and Heisenberg forms of the interimpurity exchange interaction using continuous-time quantum Monte-Carlo and numerical renormalization-group methods. Each model exhibits a Kondo-destruction quantum critical point separating Kondo-screened and local-moment phases. For antiferromagnetic interimpurity exchange interactions, singlet pairing is found to be enhanced in the vicinity of the transition. Implications of this result for heavy-fermion superconductivity are discussed.

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J. H. Pixley, Lili Deng, Kevin Ingersent, Qimiao Si. 2015-12-03. Pairing Correlations Near a Kondo-Destruction Quantum Critical Point. https://doi.org/10.1103/physrevb.91.201109

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