Hybridization fluctuations in the half-filled periodic Anderson model

TL;DR

This study uses determinant Quantum Monte Carlo simulations to explore hybridization fluctuations in the half-filled periodic Anderson model, revealing a crossover between different electronic states and connecting experimental observations with theoretical insights.

Contribution

It provides the first numerical evidence linking hybridization fluctuations to experimental phenomena in heavy fermion systems, proposing a unified interpretative framework.

Findings

Identification of a crossover regime between unhybridized and hybridized states.

Observation of nonlocal hybridization fluctuations and band bending.

Establishment of the Kondo insulating state at low temperatures.

Abstract

Motivated by recent photoemission and pump-probe experiments, we report determinant Quantum Monte Carlo simulations of hybridization fluctuations in the half-filled periodic Anderson model. A tentative phase diagram is constructed based solely on hybridization fluctuation spectra and reveals a crossover regime between an unhybridized selective Mott state and a fully hybridized Kondo insulating state. This intermediate phase exhibits nonlocal hybridization fluctuations and consequentially the so-called "band bending" and a direct hybridization gap as observed in angle-resolved photoemission spectroscopy and optical conductivity. This connects the band bending with the nonlocal hybridization fluctuations as proposed in latest ultrafast optical pump-probe experiment. The Kondo insulating state is only established at lower temperatures with the development of sufficiently strong inter-site hybridization correlations. Our work suggests a unified picture for interpreting recent photoemission, pump-probe, and optical observations and provides numerical evidences for the importance of hybridization fluctuations in heavy fermion physics.