Search for novel order in URu2Si2 by neutron scattering

TL;DR

This study used high-resolution neutron diffraction to search for hidden order in URu2Si2 but found no new structural features, confirming the absence of additional order parameters beyond known antiferromagnetism.

Contribution

The paper provides the most sensitive neutron scattering measurements to date, setting upper limits on possible hidden order structures in URu2Si2.

Findings

No incommensurate or short-range order detected

Only known tiny antiferromagnetic moment observed

Experimental sensitivity limits set constraints on hidden order

Abstract

We have made extensive reciprocal space maps in the heavy-fermion superconductor URu2Si2 using high-resolution time-of-flight single-crystal neutron diffraction to search for signs of a hidden order parameter related to the 17.5 K phase transition. Within the present sensitivity of the experiment (0.007 uB/U-ion for sharp peaks), no additional features such as incommensurate structures or short-range order have been found in the (h0l) or (hhl) scattering planes. The only additional low-temperature scattering observed was the well-known tiny antiferromagnetic moment of 0.03 uB/U-ion.