Gamma5 quasiparticles and avoided quantum criticality in U(Ru,Rh)2Si2

TL;DR

This paper investigates the behavior of quasiparticles and quantum criticality in URu2Si2 and Rh-doped variants under high magnetic fields, revealing hybridized 5f-electron bands and an itinerant electron metamagnetism near a critical field.

Contribution

It introduces new insights into quasiparticle band formation and quantum criticality in URu2Si2 through combined specific heat and de Haas-van Alphen data analysis.

Findings

Quasiparticle bands formed from 5f-electron Gamma5 doublets and conduction electrons.

Identification of a quantum critical point at 34-37 T.

Field-induced phases destabilize the quantum critical point.

Abstract

We discuss recent specific heat data in high magnetic fields on URu2Si2 and 4% Rh-doped URu2Si2 as well as previously published de Haas-van Alphen data at lower magnetic fields in pure URu2Si2; both of which are consistent with quasiparticle bands formed from a hybridization between 5f-electron Gamma5 doublets and regular conduction electrons. The system exhibits itinerant electron metamagnetism that gives rise to a putative quantum critical point at \~ 34 -37 T (depending on the % of Rh) that is subsequently unstable to field-induced phases