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arXiv · 1608.03071

Junction of three off-critical quantum Ising chains and two-channel Kondo effect in a superconductor

Domenico Giuliano·Gabriele Campagnano·Arturo Tagliacozzo
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Abstract

We show that a junction of three off-critical quantum Ising chains can be regarded as a quantum spin chain realization of the two-channel spin-1/2 overscreened Kondo effect with two superconducting leads. We prove that, as long as the Kondo temperature is larger than the superconducting gap, the equivalent Kondo model flows towards the 2 channel Kondo fixed point. We argue that our system provides the first controlled realization of 2 channel Kondo effect with superconducting leads. This, besides its the theoretical interest, is of importance for potential applications to a number of context, including the analysis of the quantum entanglement properties of a Kondo system.

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Domenico Giuliano, Gabriele Campagnano, Arturo Tagliacozzo. 2016-08-10. Junction of three off-critical quantum Ising chains and two-channel Kondo effect in a superconductor. https://doi.org/10.1140/epjb/e2016-70477-7

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