Competing Ordered Phases in URu2Si2: Hydrostatic Pressure and Re-substitution

A persistent kink in the pressure dependence of the \hidden order" (HO) transition temperature of URu2-xRexSi2 is observed at a critical pressure Pc=15 kbar for 0 < x < 0.08. In URu2Si2, the kink at Pc is accompanied by the destruction of superconductivity; a change in the magnitude of a spin excitation gap, determined from electrical resistivity measurements; and a complete gapping of a portion of the Fermi surface (FS), inferred from a change in scattering and the competition between the HO state and superconductivity for FS fraction

Inelastic contribution of the resistivity in the hidden order in URu2Si2

In the hidden order of URu2Si2 the resistivity at very low temperature shows no T^2 behavior above the transition to superconductivity. However, when entering the antiferromagnetic phase, the Fermi liquid behavior is recovered. We discuss the change of the inelastic term when entering the AF phase with pressure considering the temperature dependence of the Grueneisen parameter at ambient pressure and the influence of superconductivity by an extrapolation of high field data.Comment: 5 pages, 2 figures, SCES conference proceedin

The effect of the 4f-quadrupole charge distribution on the electrical resistivity of TmSb

Nous avons étudié les interactions entre électrons de conduction et les électrons localisés 4f dans le composé TmSb par la mesure de la variation en température de la résistivité électrique. On montre que la diffusion due à la distribution de charge quadrupolaire des électrons 4f donne une contribution à la résistivité du même ordre de grandeur que le processus d'échange habituel. On trouve un bon accord entre théorie et expérience quand cette contribution est prise en compte.The interaction between the conduction electrons and the localized 4f-electrons in TmSb has been investigated by measuring the temperature variation in the electrical resistivity. It is shown that the scattering by the 4f-quadrupole charge distribution in Tm gives a contribution to the resistivity of the same order of magnitude as the usual exchange scattering processes. Good agreement is obtained between theory and experiment when this contribution is taken into account