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arXiv · 0805.0235

Kondo polarons in a one-dimensional Fermi gas

Austen Lamacraft
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Abstract

We consider the motion of a spin-1/2 impurity in a one-dimensional gas of spin-1/2 fermions. For antiferromagnetic interaction between the impurity and the fermions, the low temperature behavior of the system is governed by the two-channel Kondo effect, leading to the impurity becoming completely opaque to the spin excitations of the gas. As well as the known spectral signatures of the two-channel Kondo effect, we find that the low temperature mobility of the resulting `Kondo polaron' takes the universal form $μ\to \frac{3\hbar v_F^2}{2πk_B^2T^2}$, in sharp contrast to the spinless case where $μ\propto T^{-4}$.

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Austen Lamacraft. 2009-07-19. Kondo polarons in a one-dimensional Fermi gas. https://doi.org/10.1103/physrevlett.101.225301

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