Recent experimental studies in URuSi

Kambe, Shinsaku  ; Tokunaga, Yo  ; Sakai, Hironori   ; Aoki, Dai*; Salce, B.*; Bourdarot, F.*; Matsuda, Tatsuma*; Haga, Yoshinori   ; Braithwaite, D.*; Flouquet, J.*; Brison, J.-P.*; Fisk, Z.; Walstedt, R. E.*

Recent two experimental investigations in URuSi will be presented. In first part, the temperature dependence of the thermal expansion coefficient will be presented in URuSi under uniaxial pressure along the [100] and [110] directions up to GPa. For both cases, the hidden order phase transition temperature increases with increasing uniaxial pressure. An antiferromagnetically ordered phase appears at above the critical pressure GPa for uniaxial pressure along the [100] direction, whereas no antiferromagnetic transition is detected up to GPa for uniaxial pressure along the [110] direction, indicating that the critical pressure is beyond GPa for the [110] case. 2-fold intrinsic (mono-domain) susceptibility anisotropy in the basal plane, a value times smaller than that obtained from recent susceptibility measurements.