Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Rapid Suppression of the Energy Gap and the Possibility of a Gapless Hidden Order State in URu2-xRexSi2



S. Ran, G. M. Schmiedeshoff, N. Pouse, I. Jeon, Nicholas Butch, R. B. Adhikari, C. C. Almasan, M. B. Maple


We investigated the energy gap associated with the hidden order (HO) phase and the Gruneisen ratio in the URu2-xRexSi2 system using a combination of thermal expansion coefficient and specific heat measurements. As the HO phase transition is suppressed to lower temperature, the ratio between the energy gap and the HO transition temperature decreases by three-fold. This rapid suppression of the energy gap potentially leads to a scenario of a "gapless" HO state, in which the energy gap of the HP phase vanishes before the HO transition temperature is suppressed to 0 K. We also investigated the Gruneisen ratio in the vicinity of the Re substituent composition where the HO is suppressed. The Gruneisen ratio shows divergent behavior at x = 0.12 and 0.15, providing evidence for the existence of a quantum critical point, which is consistent with our hypothesis of a "gapless" HO state.
Philosophical Magazine


correlated electron, heavy fermion, hidden order


Ran, S. , Schmiedeshoff, G. , Pouse, N. , Jeon, I. , Butch, N. , Adhikari, R. , Almasan, C. and Maple, M. (2019), Rapid Suppression of the Energy Gap and the Possibility of a Gapless Hidden Order State in URu<sub>2-x</sub>Re<sub>x</sub>Si<sub>2</sub>, Philosophical Magazine, [online], (Accessed June 24, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created March 31, 2019, Updated October 12, 2021