Bulk Superconductivity below 6K in PdBi2Te3 topological single crystal

TL;DR

This study reports the discovery of bulk superconductivity below 6K in PdBi2Te3 single crystals, confirmed through various measurements and structural analysis, indicating potential for topological superconductor applications.

Contribution

First demonstration of bulk superconductivity in PdBi2Te3 single crystals with detailed characterization of its superconducting parameters.

Findings

Superconductivity observed below 6K in PdBi2Te3

Type II superconductivity confirmed by magnetization measurements

Critical fields and parameters quantified for the first time

Abstract

We study the structural and bulk superconducting properties of self flux grown PdBi2Te3 single crystal. Phase purity of as grown crystal is confirmed by Rietveld refinement of gently crushed powder XRD of the same. PdBi2Te3 crystallizes in rhombohedral structure with R-3 m space group along with small impurity of Bi. Scanning Electron Microscopy (SEM) images showed layered structure and the elemental analysis by energy dispersive X Ray analysis (EDAX) done on same confirmed the stoichiometry to be near to PdBi2Te3. Characteristic vibrational modes viz. A11g, Eg2, A21g are clearly observed in Raman spectrum, and are slightly shifted from that as in case of Bi2Te3. Bulk superconductivity is confirmed by FC and ZFC magnetization measurements (M-T) exhibiting diamagnetic transition with Tconset at around 6K. M-H plots at different temperatures of 2K, 2.5K, 3K, 3.5K, 4K, 4.5K, 5K and 6K showed clear opening of the loop right up to 6K. Both M-T and M-H clearly establish the appearance of bulk type II superconductivity below 6K in studied PdBi2Te3. The lower critical field Hc1 and upper critical field Hc2 are at 180Oe at 4800Oe respectively at 2K for as grown PdBi2Te3 crystal. Other critical parameters of superconductivity such as coherence length, penetration depth and kappa parameter are also calculated.