Topological Electronic and phononic chiral edge states in SiTc Crystal

TL;DR

This paper explores the topological electronic and phononic properties of SiTc crystal, revealing multifold degeneracies, Weyl points, and nontrivial bosonic modes, highlighting its potential for studying combined fermionic and bosonic topological phenomena.

Contribution

The study provides the first comprehensive analysis of both electronic and phononic topological states in SiTc, identifying multiple topological nodes and surface states using first-principles calculations.

Findings

Multiple high-fold degeneracies and topological nodes in electronic and phononic spectra

Identification of Weyl points and chiral surface states in electronic structure

Discovery of topologically nontrivial bosonic modes with Fermi arc features

Abstract

Topological materials hosting multifold fermions and bosons have emerged as a rich platform for exploring unconventional quasiparticles and transport phenomena. In this work, we investigate the chiral crystal SiTc using first-principles density functional theory and symmetry-based analysis to explore its topological electronic and phononic properties. Our study identifies multiple high-fold degeneracies and topological nodes in both the electronic band structure and phonon dispersion. We have analyzed the impact of spin-orbit coupling on the evolution of band crossing and identified Weyl points and their associated chiralities. Surface electronic states, Fermi arcs, Berry curvature distributions, and intrinsic spin Hall conductivity are computed to probe the topological response. On the phononic side, we uncover topologically nontrivial bosonic modes and corresponding longest possible Fermi arc features. These results establish SiTc as a promising candidate that simultaneously hosts topological fermionic and bosonic excitations, offering new opportunities for investigating the interplay between electronic and phononic topology.