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arXiv · 1306.6563

Quantum phase transition between one-channel and two-channel Kondo polarons

Julian Rincon·Daniel J. Garcia·K. Hallberg·Matthias Vojta
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Abstract

For a mobile spin-1/2 impurity, coupled antiferromagnetically to a one-dimensional gas of fermions, perturbative ideas have been used to argue in favor of two-channel Kondo behavior of the impurity spin. Here we combine general considerations and extensive numerical simulations to show that the problem displays a novel quantum phase transition between two-channel and one-channel Kondo screening upon increasing the Kondo coupling. We construct a ground-state phase diagram and discuss the various non-trivial crossovers as well as possible experimental realizations.

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Julian Rincon, Daniel J. Garcia, K. Hallberg, Matthias Vojta. 2013-06-27. Quantum phase transition between one-channel and two-channel Kondo polarons. https://doi.org/10.1103/physrevb.88.140407

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