Finite-temperature spectra and quasiparticle interference in Kondo lattices: From light electrons to coherent heavy quasiparticles

TL;DR

This paper models the temperature-dependent evolution of electronic spectra and quasiparticle interference in Kondo lattices, revealing a dynamical crossover from light electrons to coherent heavy quasiparticles, relevant for interpreting heavy-fermion experiments.

Contribution

It provides a comprehensive theoretical analysis of the spectral and interference phenomena in Kondo lattices across all temperatures using dynamical mean-field theory.

Findings

Identification of a temperature-dependent crossover to heavy quasiparticles

Detailed Fermi-surface reconstruction near the Kondo temperature

Characterization of the incoherent regime in heavy-fermion systems

Abstract

Recent advances in scanning tunneling spectroscopy performed on heavy-fermion metals provide a window onto local electronic properties of composite heavy-electron quasiparticles. Here we theoretically investigate the energy and temperature evolution of single-particle spectra and their quasiparticle interference caused by point-like impurities in the framework of a periodic Anderson model. By numerically solving dynamical-mean-field-theory equations, we are able to access all temperatures and to capture the crossover from weakly interacting c and f electrons to fully coherent heavy quasiparticles. Remarkably, this crossover occurs in a dynamical fashion at an energy-dependent crossover temperature. We study in detail the associated Fermi-surface reconstruction and characterize the incoherent regime near the Kondo temperature. Finally, we link our results to current heavy-fermion experiments.