The Kondo-lattice state and non-Fermi-liquid behavior in the presence of Van Hove singularities

TL;DR

This paper investigates how Van Hove singularities influence the Kondo lattice behavior, revealing enhanced non-Fermi-liquid regions and significant reductions in magnetic moments and spin-fluctuation frequencies.

Contribution

It introduces a scaling approach that accounts for Van Hove singularities, showing their impact on magnetic phases and non-Fermi-liquid behavior in Kondo lattices.

Findings

VHS increase non-Fermi-liquid region due to magnon softening

Effective coupling remains moderate despite renormalization

Magnetic moments and spin-fluctuation frequencies can decrease significantly

Abstract

A scaling consideration of the Kondo lattices is performed with account of logarithmic Van Hove singularities (VHS) in the electron density of states. The scaling trajectories are presented for different magnetic phases. It is demonstrated that VHS lead to a considerable increase of the non-Fermi-liquid behavior region owing to softening of magnon branches during the renormalization process. Although the effective coupling constant remains moderate, renormalized magnetic moment and spin-fluctuation frequency can decrease by several orders of magnitude. A possible application to f-systems and weak itinerant magnets is discussed.