Topological Electronic and phononic chiral edge states in SiTc Crystal

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.