A theoretical study of tunneling conductance in ${\mathrm{PrOs}}_4{\mathrm{Sb}}_{12}$ superconducting junctions

The tunnel conductance in normal-metal/insulator/${\mathrm{ProS}}_4{\mathrm{Sb}}_{12}$ junctions is theoretically studied, where skutterudite ${\mathrm{ProS}}_4{\mathrm{Sb}}_{12}$ is considered to be an unconventional superconductor. The conductance is calculated for several pair potentials which have been proposed in recent work. The results show that the conductance is sensitive to the relation between the direction of electric currents and the position of point nodes. The conductance spectra often deviate from the shape of bulk density of states. The sub gap spectra have peak structures in the case of the spin-triplet pair potentials. The results indicate that the tunnel conductance is a useful tool to obtain information of the pairing symmetry.