Exact Thermodynamics of Disordered Impurities in Quantum Spin Chains

TL;DR

This paper provides exact thermodynamic calculations for disordered magnetic impurities in quantum spin chains, revealing how disorder strength affects impurity moment quenching and non-Fermi-liquid behavior, with implications for experimental systems.

Contribution

It presents exact solutions for thermodynamics of disordered impurities in quantum spin chains, a novel approach for arbitrary temperature and magnetic field conditions.

Findings

Strong disorder prevents impurity moment quenching.

Weak disorder maintains screening with non-Fermi-liquid behavior.

Results align with disordered Kondo effect experiments.

Abstract

Exact results for the thermodynamic properties of ensembles of magnetic impurities with randomly distributed host-impurity couplings in the quantum antiferromagnetic Heisenberg model are presented. Exact calculations are done for arbitrary values of temperature and external magnetic field. We have shown that for strong disorder the quenching of the impurity moments is absent. For weak disorder the screening persists, but with the critical non-Fermi-liquid behaviors of the magnetic susceptibility and specific heat. A comparison with the disordered Kondo effect experiments in dirty metallic alloys is performed.