Scaling theory of magnetism in frustrated Kondo lattices

TL;DR

This paper develops a scaling theory for frustrated Kondo lattices, exploring quantum phase transitions and the conditions for magnetic order, spin-liquid, and Fermi-liquid states, with implications for non-Fermi-liquid behavior.

Contribution

It introduces a scaling framework that accounts for magnon and spin dynamics, revealing multiple quantum phase transitions in frustrated Kondo lattices.

Findings

Multiple quantum phase transitions into spin-liquid and Fermi-liquid states.

Magnetic moment renormalization can be very large in the ordered phase.

Moderate renormalization of spin fluctuation frequency supports the scaling approach.

Abstract

A scaling theory of the Kondo lattices with frustrated exchange interactions is developed, criterium of antiferromagnetic ordering and quantum-disordered state being investigated. The calculations taking into account magnon and incoherent spin dynamics are performed. Depending on the bare model parameters, one or two quantum phase transitions into non-magnetic spin-liquid and Kondo Fermi-liquid ground states can occur with increasing the bare coupling constant. Whereas the renormalization of the magnetic moment in the ordered phase can reach orders of magnitude, spin fluctuation frequency and coupling constant are moderately renormalized in the spin-liquid phase. This justifies application of the scaling approach. Possibility of a non-Fermi-liquid behavior is treated.