Hidden order pseudogap in URu$_2$Si$_2$

TL;DR

This paper provides evidence for a hidden order pseudogap in URu2Si2 between 25 K and 17.5 K, suggesting fluctuations of the hidden order gap precede a likely second-order phase transition.

Contribution

It introduces a model linking hidden order gap fluctuations to experimental signatures, clarifying the nature of the transition in URu2Si2.

Findings

Evidence for a hidden order pseudogap between 25 K and 17.5 K

Fluctuations of the hidden order gap influence observable properties

Transition into hidden order phase is likely second order

Abstract

Through an analysis and modeling of data from various experimental techniques, we present clear evidence for the presence of a hidden order pseudogap in \U in the temperature range between 25 K and 17.5 K. Considering fluctuations of the hidden order energy gap at the transition as the origin of the pseudogap, we evaluate the effects that gap fluctuations would produce on observables like tunneling conductance, neutron scattering and nuclear resonance, and relate them to the experimental findings. We show that the transition into hidden order phase is likely second order and is preceded by the onset of non-coherent hidden order fluctuations.