Magnetic ordering and non-Fermi-liquid behavior in the multichannel Kondo-lattice model

TL;DR

This paper derives two-loop scaling equations for the multichannel Kondo lattice, revealing mechanisms for non-Fermi-liquid behavior influenced by magnetic ordering, Van Hove singularities, and dimensionality, with implications for electronic and magnetic properties.

Contribution

It introduces a detailed two-loop analysis of the Kondo lattice, highlighting the role of spin dynamics and Van Hove singularities in non-Fermi-liquid behavior across different magnetic phases.

Findings

Non-Fermi-liquid behavior occurs near a weak-coupling fixed point.

Magnetic ordering type and dimensionality significantly influence NFL conditions.

Van Hove singularities impact magnon spectral functions and electronic properties.

Abstract

Scaling equations for the Kondo lattice in the paramagnetic and magnetically ordered phases are derived to two-loop order with account of spin dynamics. The results are applied to describe various mechanisms of the non-Fermi-liquid (NFL) behavior in the multichannel Kondo-lattice model where a fixed point occurs in the weak-coupling region. The corresponding temperature dependences of electronic and magnetic properties are discussed. The model describes naturally formation of a magnetic state with soft boson mode and small moment value. An important role of Van Hove singularities in the magnon spectral function is demonstrated. The results are rather sensitive to the type of magnetic ordering and space dimensionality, the conditions for NFL behavior being more favorable in the antiferromagnetic and 2D cases.