Research Paper: Topological Phase Transition of InSb and InBi Under Nonhydrostatic Lattice Expansion

• Published in: Fīzīk-i kārburdī Īrān (Online) Vol. 14; no. 3; pp. 106 - 121
• Main Authors: Saba Ahmadvand, Shirin Namjoo
• Format: Journal Article
• Language: Persian
• Published: Alzahra University 01-09-2024
• Subjects: band inversion; density functional theory; iii-v compounds; non-hydrostatic lattice expansion; topological semiconductors
• ISSN: 2783-1043; 2783-1051
• DOI: 10.22051/ijap.2024.46666.1397

This study investigated the topological phase transition of InSb and InBi under a non-hydrostatic lattice using density functional theory and the WIEN2K code. The results of examining the band structure of InSb and InBi employing the mBJGGA exchange-correlation potential indicate that InSb is a semiconductor with a small band gap and normal band order at the Γ point. At the same time, InBi is a metal with band inversion at the Brillouin zone center. To transform these compounds into topological semiconductors, the lattice of these compounds is subjected to non-hydrostatic lattice expansion. Non-hydrostatic lattice expansion is applied in two ways. Firstly, the lattice constants are expanded in the ab plane while keeping the lattice constant along the c-axis constant. Then, the lattice constant is expanded along the c-axis while keeping the lattice constant in the ab plane constant. The calculations indicate that under the influence of both types of non-hydrostatic lattice expansion, with the breaking of cubic symmetry, a transition towards topological semiconductors occurs.