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.
, Schmiedeshoff, G.
, Pouse, N.
, Jeon, I.
, Butch, N.
, Adhikari, R.
, Almasan, C.
and Maple, M.
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], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=924634
(Accessed December 4, 2023)