Superconductivity and heavy fermion behavior in PrOs4Sb12 -: art. no. 100506

Superconductivity has been observed in PrOs4Sb12 at T-C =1.85 K and appears to involve heavy fermion quasiparticles with an effective mass m*similar to50 m(e) as inferred from the jump in the specific heat at T-C, the upper critical field near T-C, and the normal state electronic specific heat. Thermodynamic and transport measurements suggest that the heavy fermion state has a quadrupolar origin, although a magnetic origin cannot be completely ruled out.