Equivalence of single-particle and transport lifetimes from hybridization fluctuations

TL;DR

This paper shows that in a quantum critical material with hybridization fluctuations, both single-particle and charge transport lifetimes exhibit similar quasi-linear temperature dependence, challenging previous assumptions about momentum dependence.

Contribution

It demonstrates that hybridization fluctuations can produce equivalent temperature dependence for both lifetimes despite strong momentum dependence.

Findings

Both lifetimes show quasi-linear temperature dependence.

Hybridization fluctuations enable charge transport and single-particle lifetimes to be equivalent.

Challenges the notion that momentum dependence prevents similar temperature behavior.

Abstract

Single band theories of quantum criticality successfully describe a single-particle lifetime with non-Fermi liquid temperature dependence. But, they fail to obtain a charge transport rate with the same dependence unless the interaction is assumed to be momentum independent. Here we demonstrate that a quantum critical material, with a long range mode that transmutes electrons between light and heavy bands, exhibits a quasi-linear temperature dependence for {\it both} the single-particle and the charge transport lifetimes, despite the strong momentum dependence of the interaction.