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arXiv · 2204.04669

Generalized Calogero-Sutherland models for Kondo physics in the Luttinger liquid

Abstract

We propose a series of models with inverse-square interactions, for which the ground states have an exact closed form, that describe one localized spin-$1/2$ Kondo impurity coupled to Luttinger liquids of itinerant bosons or fermions in the continuum or on a lattice. The model Hamiltonians contain two parts: a two-component Calogero-Sutherland model with open boundary condition in the continuum or a long-range $t \textendash J$-type model on the lattice, and long-range Kondo couplings between the impurity and the particles. The wave functions of the ground states in a certain basis have Jastrow product forms with powers depending on the particle statistics. It is shown that the wave functions can be expressed as chiral correlators of certain conformal field theories, which reveals that the particles are fractionalized to fully screen the Kondo impurity. This insight would be very useful in future studies on the very difficult problem of Kondo physics with interacting baths.

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Hua-Chen Zhang, Ying-Hai Wu, Hong-Hao Tu. 2022-04-10. Generalized Calogero-Sutherland models for Kondo physics in the Luttinger liquid. https://doi.org/10.1103/physrevb.108.l161102

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