Deconfined quantum criticality in the two dimensional Kondo lattice model

TL;DR

This paper explores a novel type of quantum phase transition in a two-dimensional Kondo lattice, where fractionalization of particles and emergent gauge fields lead to unique non-Fermi liquid behavior at criticality.

Contribution

It introduces a deconfined quantum criticality framework for the 2D Kondo lattice, incorporating fractionalized excitations and emergent gauge fields, advancing understanding of quantum critical points.

Findings

Predicts non-Fermi liquid behavior near the critical point

Recovers Fermi liquid physics away from criticality

Proposes a critical field theory with fractionalized fields

Abstract

We investigate the continuous quantum phase transition from an antiferromagnetic metal to a heavy fermion liquid based on the Kondo lattice model in two dimensions. We propose that antiferromagnetic spin fluctuations and conduction electrons fractionalize into neutral bosonic spinons and charged spinless fermions at the quantum critical point. This deconfined quantum criticality leads us to establish a critical field theory in terms of the fractionalized fields interacting via emergent U(1) gauge fields. The critical field theory not only predicts non-Fermi liquid physics near the quantum critical point but also recovers Fermi liquid physics away from the quantum critical point.