Evidence of phase stability, topological phonon and temperature-induced topological phase transition in rocksalt SnS and SnSe

Abstract

Both SnS and SnSe have been experimentally and theoretically confirmed as topological crystalline insulators in native rocksalt structure. Here, phononic structure, thermodynamical properties and temperature dependent electron-phonon interaction (EPI) have investigated for both the materials in rocksalt phase. Previously performed theoretical studies have predicted the phase instability of SnS in this crystal structure at ambient condition. But, after a detailed study performing on the phonon calculation of SnS, we have predicted the phase stability of SnS with considering the Sn 4$p$ orbitals as valence states in $ab-initio$ calculation. The importance of long range Coulomb forces along with the themodynamical properties are also described in detailed for both materials. The preliminary evidence of topological phonon is found along X-W direction, where the linear band touching is observed as compared to type II Weyl phononic material ZnSe. The topological phase transition is seen for these materials due to EPI, where non-linear temperature dependent bandgap is estimated. The predicted value of transition temperature for SnS (SnSe) is found to be $\sim$700 K, where after this temperature the non-trivial to trivial topological phase is seen. The strength of EPI shows more stronger impact on the electronic structure of SnS than SnSe material. The reason of non-linear behaviour of bandgap with rise in temperature is discussed with the help of temperature dependent linewidths and lineshifts of conduction band and valence band due to EPI. The present study reveals the phase stability of SnS along with the comparative study of thermal effect on EPI of SnS and SnSe. Further, the possibility of temperature induced topological phase transition provides one of important behaviour to apply these two materials for device making application.

References in corpus (12)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Topological Crystalline Insulators
• Distribution of phonon lifetime in Brillouin zone
• The space group classification of topological band insulators
• Infrared Reflectance Spectrum of BN Calculated from First Principles
• Chemical and Lattice Stability of the Tin Sulfides
• Three-dimensional Dirac Phonons with Inversion Symmetry
• Resonance fluorescence of GaAs quantum dots with near-unity photon indistinguishability
• $C_n$-symmetric higher-order topological crystalline insulators in atomically thin transition-metal dichalcogenides
• Exploring temperature dependent electron-electron interaction of topological crystalline insulators (SnS and SnSe) within Matsubara-time domain

Cited by in corpus (1)

• Topological electronic structure of twin boundaries and twinning superlattices in the SnTe material class