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arXiv:1202.5545 · Physical Review B

Magnetic phases in the one-dimensional Kondo chain on a metallic surface

Alejandro M. Lobos, Miguel A. Cazalilla, Piotr Chudziński

Published Jul 30, 2012• 24 citations
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Abstract

We study the low-temperature properties of a one-dimensional spin-$1/2$ chain of magnetic impurities coupled to a (normal) metal environment by means of anisotropic Kondo exchange. In the case of easy-plane anisotropy, we obtain the phase diagram of this system at $T=0$. We show that the in-plane Kondo coupling destabilizes the Tomonaga-Luttinger phase of the spin chain, and leads to two different phases: (i) At strong Kondo coupling, the spins in the chain form Kondo singlets and become screened by the metallic environment, and (ii) at weak and intermediate Kondo coupling, we find a novel dissipative phase characterized by diffusive gapless spin excitations. The two phases are separated by a quantum critical point of the Wilson-Fisher universality class with dynamical exponent $z\ensuremath{\simeq}2$.

DOI
10.1103/physrevb.86.035455

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