Jean-Pascal Brison

Multiband superconductivity in the heavy fermion compound PrOs4Sb12.

The thermal conductivity of the heavy fermion superconductor Pr(Os(4)Sb(12) was measured down to T(c)/40 throughout the vortex state. At lowest temperatures and for magnetic fields H approximately 0.07H(c2), already 40% of the normal state thermal conductivity is restored. This behavior (similar to that observed in MgB2) is a clear signature of multiband superconductivity in this compound.

Pressure induced effects on the fermi surface of superconducting 2H-NbSe2

The pressure dependence of the critical temperature T(c) and upper critical field H(c2)(T) has been measured up to 19 GPa in the layered superconducting material 2H-NbSe2. T(c)(P) has a maximum at 10.5 GPa, well above the pressure for the suppression of the charge density wave (CDW) order. Using an effective two-band model to fit H(c2)(T), we obtain the pressure dependence of the anisotropy in the electron-phonon coupling and Fermi velocities, which reveals the peculiar interplay between CDW order, Fermi surface complexity, and superconductivity in this system.

Superconducting phase diagram of the filled skuterrudite PrOs4Sb12

We present new measurements of the specific heat of the heavy fermion superconductor PrOs4Sb12, on a sample which exhibits two sharp distinct anomalies at Tc1= 1.89K and Tc2= 1.72K. They are used to draw a precise magnetic field-temperature superconducting phase diagram ofPrOs4Sb12 down to 350~mK. We discuss the superconducting phase diagram of PrOs4Sb12 and its possible relation with an unconventional superconducting order parameter. We give a detailed analysis of Hc2(T), which shows paramagnetic limitation (a support for even parity pairing) and multiband effects.

Superconducting PrOs4Sb12: a thermal conductivity study.

The superconducting state of the heavy fermion PrOs4Sb12 is studied by heat transport measurements on a highly homogeneous single crystal exhibiting only one transition peak in the specific heat. The field and temperature dependence of the thermal conductivity confirm multiband superconductivity and point to fully open gaps on the whole Fermi surface.

High-pressure phase diagrams of CeRhIn5 and CeCoIn5 studied by ac calorimetry

The pressure-temperature phase diagrams of the heavy fermion antiferromagnet CeRhIn

Thermal conductivity and gap structure of the superconducting phases of UPt3

_5

Penetration depth study of superconducting gap structure of 2H-NbSe2

and the heavy fermion superconductor CeCoIn

Pressure dependence of the upper critical field of Mg B 2 and of Y Ni 2 B 2 C

_5

Pressure dependence of superconducting critical temperature and upper critical field of 2H-NbS2

have been studied under hydrostatic pressure by ac calorimetry and ac susceptibility measurements using diamond anvil cells with argon as pressure medium. In CeRhIn

Phonon-mediated anisotropic superconductivity in the Y and Lu nickel borocarbides

_5