Locally critical point in an anisotropic Kondo lattice

TL;DR

This paper numerically identifies a locally quantum critical point in an anisotropic Kondo lattice, revealing fractional critical exponents consistent with heavy fermion experiments.

Contribution

First numerical demonstration of a locally quantum critical point in an anisotropic Kondo lattice model with detailed critical behavior analysis.

Findings

Identification of a locally quantum critical point embedded in magnetic criticality

Fractional critical exponent for dynamical spin susceptibility

Agreement with experimental heavy fermion data

Abstract

We report the first numerical identification of a locally quantum critical point, at which the criticality of the local Kondo physics is embedded in that associated with a magnetic ordering. We are able to numerically access the quantum critical behavior by focusing on a Kondo-lattice model with Ising anisotropy. We also establish that the critical exponent for the q-dependent dynamical spin susceptibility is fractional and compares well with the experimental value for heavy fermions.