Low energy properties of the Kondo chain in the RKKY regime

Abstract

We study the Kondo chain in the regime of high spin concentration where the low energy physics is dominated by the Ruderman–Kittel–Kasuya–Yosida interaction. As has been recently shown (Tsvelik and Yevtushenko 2015 Phys. Rev. Lett. http://dx.doi.org/10.1103/PhysRevLett.115.216402 115 http://dx.doi.org/10.1103/PhysRevLett.115.216402 ), this model has two phases with drastically different transport properties depending on the anisotropy of the exchange interaction. In particular, the helical symmetry of the fermions is spontaneously broken when the anisotropy is of the easy plane type. This leads to a parametrical suppression of the localization effects. In the present paper we substantially extend the previous theory, in particular, by analyzing a competition of forward- and backward- scattering, including into the theory short range electron interactions and calculating spin correlation functions. We discuss applicability of our theory and possible experiments which could support the theoretical findings.

Keywords

• helical symmetry
• ideal protected transport
• Kondo chain
• RKKY