Theoretical prediction of a novel Pt3Sn2S2 as a Nonmagnetic Weyl Semimetal in Kagome System

TL;DR

This paper theoretically predicts that Pt3Sn2S2, a layered kagome material, exhibits a Weyl semimetal phase with tunable electronic properties and potential thermoelectric applications, driven by spin orbit coupling and pressure effects.

Contribution

It introduces a novel Pt3Sn2S2 kagome material as a nonmagnetic Weyl semimetal with detailed stability analysis and tunable topological features, expanding the family of topological materials.

Findings

Pt3Sn2S2 is thermodynamically and mechanically stable.

The material exhibits Weyl points induced by spin orbit coupling.

High Seebeck coefficient and low thermal conductivity suggest thermoelectric potential.

Abstract

We present a detailed theoretical study of Pt3Sn2S2 a layered kagome type material inspired by recent investigation of Co3Sn2S2 reported in [Nature Communication 11, 3985 (2020) whose physical properties remain largely unexplored. Thermodynamic stability was confirmed via formation energy calculations while mechanical stability was evaluated using Voigt Reuss Hill approximation and elastic stability condition. Dynamical and thermal stability were validated through Phonon dispersion and Ab Initio Molecular Dynamics simulations with Pughs criterion classifying the material as ductile. Spin orbit coupling induced band splitting, giving rise to Weyl points and a Weyl semimetal phase accompanied by a SOC driven transition from non relativistic band touching to relativistic band touching making a topological phase shift. Under applied pressure, the coupling of spin and valley degrees of freedom generates spin valley intertwined Dirac cones enabling tunable electronic properties for spintronic and valleytronic applications. Boltzman transport calculations using AMSET reveal a high Seebeck coefficient with SOC and low thermal conductivity highlighting its potential for high performance thermoelectric devices.