Superconductivity in cubic noncentrosymmetric PdBiSe Crystal

TL;DR

This paper reports the synthesis and characterization of a cubic noncentrosymmetric PdBiSe crystal that exhibits superconductivity below 1.8 K, highlighting its potential for unconventional superconducting phases due to strong spin-orbit coupling.

Contribution

First successful growth of cubic noncentrosymmetric PdBiSe crystal demonstrating superconductivity, expanding the understanding of unconventional phases in cubic NCS materials.

Findings

Superconducting transition below 1.8 K confirmed by transport and susceptibility measurements.

PdBiSe has a cubic structure with space group P2_1 3.

High atomic number elements suggest strong Rashba-type spin-orbit coupling.

Abstract

Mixing of spin singlet and spin triplet superconducting pairing state is expected in noncentrosymmetric superconductors (NCS) due to the inherent presence of Rashba-type antisymmetric spin-orbit coupling. Unlike low symmetry (tetragonal or monoclinic) NCS, parity is isotropicaly broken in space for cubic NCS and can additionally lead to the coexistence of magnetic and superconducting state under certain conditions. Motivated with such enriched possibility of unconventional superconducting phases in cubic NCS we are reporting successful formation of single crystalline cubic noncentrosymmetric PdBiSe with lattice parameter a = 6.4316 {\AA} and space group P2_1 3 (space group no. 198) which undergoes to superconducting transition state below 1.8 K as measured by electrical transport and AC susceptibility measurements. Significant strength of Rashba-type antisymmetric spin-orbit coupling can be expected for PdBiSe due to the presence of high Z (atomic number) elements consequently making it potential candidate for unconventional superconductivity.