Tunneling Spectra of Skutterudite PrOs_4Sb_{12}

TL;DR

This paper theoretically investigates the tunneling conductance in normal-metal/insulator/PrOs$_4$Sb$_{12}$ junctions, revealing how conductance spectra depend on pairing symmetry and can help identify unconventional superconducting states.

Contribution

It provides a theoretical analysis of tunneling spectra for various proposed pairing potentials in PrOs$_4$Sb$_{12}$, highlighting their sensitivity to pairing symmetry and directional effects.

Findings

Conductance spectra are sensitive to the orientation of electric currents and point nodes.

Sub gap spectra can exhibit peak structures for spin-triplet pairings.

Tunneling conductance can serve as a diagnostic for pairing symmetry.

Abstract

The tunnel conductance in normal-metal / insulator / PrOs$_4$Sb$_{12}$ junctions is theoretically studied, where skutterudite PrOs$_4$Sb$_{12}$ is considered to be an unconventional superconductor. The conductance are calculated for several pair potentials which have been proposed in recent works. The results show that the conductance is sensitive to the relation between the direction of electric currents and the position of point nodes. We also show that the conductance spectra often deviate from the shape of the bulk density of states and that 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 an information of the pairing symmetry.