Transport properties of the heavy fermion superconductor PrOs$_{4}$Sb$_{12}$

TL;DR

This study investigates the transport properties of PrOs$_{4}$Sb$_{12}$, revealing its localized 4f-electron character and identifying a field-induced ordered phase consistent with a $ ext{Gamma}_1$ singlet ground state.

Contribution

The paper provides comprehensive transport measurements on PrOs$_{4}$Sb$_{12}$ and related compounds, establishing the nature of its electronic ground state and phase diagram.

Findings

Transport properties similar to LaOs$_{4}$Sb$_{12}$ and NdOs$_{4}$Sb$_{12}$ at high temperatures.

Transverse magnetoresistance saturates, indicating uncompensated metallic behavior.

Field-induced phase diagram supports a $ ext{Gamma}_1$ singlet crystalline electric field ground state.

Abstract

We have measured the electrical resistivity, thermoelectric power, Hall coefficient, and magnetoresistance (MR) on single crystals of PrOs$_{4}$Sb$_{12}$, LaOs$_{4}$Sb$_{12}$ and NdOs$_{4}$Sb$_{12}$. All the transport properties in PrOs$_{4}$Sb$_{12}$ are similar to those in LaOs$_{4}$Sb$_{12}$ and NdOs$_{4}$Sb$_{12}$ at high temperatures, indicating the localized character of 4$f$-electrons. The transverse MR both in LaOs$_{4}$Sb$_{12}$ and PrOs$_{4}$Sb$_{12}$ tends to saturate for wide field directions, indicating these compounds to be uncompensated metals with no open orbit. We have determined the phase diagram of the field induced ordered phase by the MR measurement for all the principle field directions, which indicates an unambiguous evidence for the $\Gamma_{\rm 1}$ singlet crystalline electric field ground state.