Neutron Scattering Study of URu$_{2-x}$Re$_x$Si$_2$ with $x$ = 0.10: Driving Order towards Quantum Criticality

TL;DR

This neutron scattering study investigates how Re-doping in URu2Si2 influences hidden order and quantum criticality, revealing persistent incommensurate fluctuations and weakened hidden order near the quantum critical point.

Contribution

It provides new insights into the evolution of magnetic fluctuations and hidden order in URu2Si2 with Re-doping approaching quantum criticality.

Findings

Incommensurate fluctuations remain robust near the quantum critical point.

Hidden order weakens and slows down as Re doping increases.

Hidden order survives at x=0.10, unlike under pressure or Rh-doping.

Abstract

We report inelastic neutron scattering measurements in the hidden order state of URu$_{2-x}$Re$_x$Si$_2$ with $x$ = 0.10. We observe that towards the ferromagnetic quantum critical point induced by the negative chemical pressure of Re-doping, the gapped incommensurate fluctuations are robust and comparable in intensity to the parent material. As the Re doping moves the system toward the quantum critical point, the commensurate spin fluctuations related to hidden order weaken, display a shortened lifetime and slow down. Halfway to the quantum critical point, the hidden order phase survives, albeit weakened, in contrast to its destruction by hydrostatic pressure and by positive chemical pressure from Rh-doping.