High-field studies of the Pd-based Superconductor Ta$_4$Pd$_3$Te$_{16}$

The layered Pd-based ternary chalcogenide Ta$_4$Pd$_3$Te$_{16}$ (TPT) has not gotten much of attention since its first synthesis in 1997. Recently, TPT was found to turn superconducting (SC) below a critical temperature of $T_c=4.5\,$K and up to $6.5\,$K under pressure. The layered material has an orthorhombic crystal structure and the main conduction channel is suspected to run along one dimensional (1D) PdTe-chains. Band structure calculations find multiple bands at the Fermi level including 1D sheets. One of the striking features in the family of M$_2$Pd$_x$Q$_5$ (M$=$Nb and Ta, Q$=$S and Se) is a very enhanced upper SC critical field $H_{c2}$. To understand the mechanism behind this enhancement TPT is of special interest since it has a similarly complex structure but much lower $H_{c2}$. Anomalous thermal transport properties and a significant anisotropy in $H_{c2}$ have been interpret in terms of an unconventional SC ground state present in TPT. Here we report studies of normal-state magnetotransport and magnetic torque in high fields that disclose details of TPT's electronic structure enabling us to speculate about the origin of SC in this compound.