The suppression of hidden order and onset of ferromagnetism in URu2Si2 via Re substitution

TL;DR

Re substitution in URu2Si2 suppresses hidden order and induces ferromagnetism, revealing complex interplay between Kondo effects and magnetic phases near a critical concentration.

Contribution

This study demonstrates how Re substitution suppresses hidden order and induces ferromagnetism in URu2Si2, providing insights into the interplay of electronic interactions in heavy fermion systems.

Findings

Hidden order transition disappears for x>0.1

Ferromagnetic order emerges near x=0.15

Critical exponents approach zero at the transition point

Abstract

Substitution of Re for Ru in the heavy fermion compound URu2Si2 suppresses the hidden order transition and gives rise to ferromagnetism at higher concentrations. The hidden order transition of URu(2-x)Re(x)Si2, tracked via specific heat and electrical resistivity measurements, decreases in temperature and broadens, and is no longer observed for x>0.1. A critical scaling analysis of the bulk magnetization indicates that the ferromagnetic ordering temperature and ordered moment are suppressed continuously towards zero at a critical concentration of x = 0.15, accompanied by the additional suppression of the critical exponents gamma and (delta-1) towards zero. This unusual trend appears to reflect the underlying interplay between Kondo and ferromagnetic interactions, and perhaps the proximity of the hidden order phase.