Discovery of Quasi One Dimensional Superconductivity in PtPb3Bi

TL;DR

This paper reports the discovery of a new quasi-one-dimensional superconductor, PtPb3Bi, with nontrivial electronic topology, type II superconductivity below 3.01 K, and potential for topological superconductivity.

Contribution

It introduces PtPb3Bi as a novel quasi 1D superconductor with nontrivial topology and detailed characterization of its electronic and superconducting properties.

Findings

Superconductivity below 3.01 K with a fully gapped s-wave state.

Presence of nontrivial band topology and surface states.

Charge density wave transition at 280 K.

Abstract

Quasi one dimensional materials provide a compelling platform where reduced dimensionality stabilizes intertwined topological and superconducting phases. Here we report superconductivity in a new Bi based quasi 1D compound, PtPb3Bi, which hosts a nontrivial electronic structure. It exhibits type II superconductivity below 3.01(1) K. Heat capacity and transverse field muon spin rotation relaxation (muSR) measurements demonstrate a fully gapped isotropic s wave state with moderate electron phonon coupling, while zero field muSR confirms the preservation of time reversal symmetry (TRS). Transport measurements reveal low carrier mobility with diffusive normal state transport. Electronic structure calculations show strong dispersion along the quasi 1D direction and relatively flatter bands in the transverse plane, giving rise to pronounced Fermi surface nesting in the kx-ky plane. Consistent with this, the compound undergoes a charge density wave transition at 280(1) K. The flow of Wannier charge centers, together with surface state dispersion, establishes nontrivial band topology. These results identify PtPb3Bi as a new quasi 1D superconductor with nontrivial electronic structure and a promising candidate for topological superconductivity.