Low temperature specific heat of the heavy fermion superconductor PrOs$_4$Sb$_{12}$
arXiv:cond-mat/0207225 · doi:10.1103/PhysRevLett.90.057001
Abstract
We report the magnetic field dependence of the low temperature specific heat of single crystals of the first Pr-based heavy fermion superconductor PrOs$_4$Sb$_{12}$. The low temperature specific heat and the magnetic phase diagram inferred from specific heat, resistivity and magnetisation provide compelling evidence of a doublet ground state and hence superconductivity mediated by quadrupolar fluctuations. This establishes PrOs$_4$Sb$_{12}$ as a very strong contender of superconductive pairing that is neither electron-phonon nor magnetically mediated.
4 pages, 4 figures