T=0 heavy fermion quantum critical point as an orbital selective Mott transition

TL;DR

This paper models the zero-temperature quantum critical point in heavy fermion systems as an orbital selective Mott transition, revealing a pseudogap formation and diverging self-energy surfaces with experimental implications.

Contribution

It introduces a cluster dynamical mean field theory approach to describe the orbital selective Mott transition in heavy fermion systems at T=0, highlighting new energy scales and experimental signatures.

Findings

Emergence of a pseudogap at the transition

Divergence of self-energy surfaces in momentum space

Predicted experimental signatures in photoemission and thermodynamics

Abstract

We describe the T=0 quantum phase transition in heavy fermion systems as an orbital selective Mott transition (OSMT) using a cluster extension of dynamical mean field theory. This transition is characterized by the emergence of a new intermediate energy scale corresponding to the opening of a pseudogap and the vanishing of the low-energy hybridization between light and heavy electrons. We identify the fingerprint of Mott physics in heavy electron systems with the appearance of surfaces in momentum space where the self-energy diverges and we derive experimental consequences of this scenario for photoemission, compressibility, optical conductivity, susceptibility and specific heat.