Quantum Criticality and Dynamical Kondo Effect in an SU(2) Anderson Lattice Model

TL;DR

This paper investigates a SU(2) Anderson lattice model using EDMFT and quantum Monte Carlo, revealing a continuous quantum phase transition of Kondo-destruction type with unique scaling and dynamical effects.

Contribution

It demonstrates a continuous quantum phase transition in an SU(2) Anderson lattice model and characterizes the dynamical Kondo effect at the quantum critical point.

Findings

Identifies a Kondo-destruction quantum critical point

Establishes anomalous scaling properties at criticality

Connects dynamical Kondo effect to local entanglement entropy

Abstract

Metallic quantum criticality often develops in strongly correlated systems with local effective degrees of freedom. In this work, we consider an Anderson lattice model with SU(2) symmetry. The model is treated by the extended dynamical mean-field theory (EDMFT) in combination with a continuous-time quantum Monte Carlo method. We demonstrate a continuous quantum phase transition, establish the ensuing quantum critical point to be of a Kondo-destruction type, and determine the anomalous scaling properties. We connect the continuous nature of the transition to a dynamical Kondo effect, which we characterize in terms of a local entanglement entropy and related properties. This effect elucidates the unusual behavior of quantum critical heavy fermion systems.