Electron–phonon coupling of the Ti3Sb compound

Abstract

Using the first-principles method based on density functional theory, we investigate the electronic, mechanical, phononic, superconducting, and topological properties of the A15 superconductor [Formula: see text]Sb with/without the inclusion of spin–orbit coupling (SOC). We find that the calculated elastic constants satisfy the Born stability criteria and the ductile nature of [Formula: see text]Sb. The result of phonon calculations reveals that the [Formula: see text] structure is dynamically stable. Sb atoms are dominated in the low-frequency region due to the mass difference between Ti and Sb from partial phonon calculations. Our electronic structure calculations show that [Formula: see text]Sb has metallic band structures with Ti-[Formula: see text] bands near the Fermi energy. The electron–phonon coupling constant ([Formula: see text]) indicates that [Formula: see text]Sb has strong electron–phonon coupling. The critical temperature ([Formula: see text]) is found to be 6.24 and 6.56 K with and without the SOC effect, respectively. Due to Ti’s relatively small SOC strength, we do not find evidence of non-trivial topology in contrast to Ta compounds such as [Formula: see text]Sb.