A First-Principles Study of Electron-Phonon Coupling of OsB₂

Abstract:

We investigated the lattice dynamics and electron-phonon coupling (EPC) of superhard material OsB₂ by first-principles linear response calculations. The calculated EPC parameters for the optical phonon modes at Г indicate that the heavy Os atoms play the most important role in deciding the superconducting behavior, and there are sizeable contributions from lighter B atoms to EPC. Our calculated EPC constant is 0.42, and the estimated superconducting transition temperature T_c is 2.1 K using the Coulomb pseudopotential μ^*=0.125, in excellent agreement with the experimental ones.

• Periodical: Applied Mechanics and Materials (Volume 597)
• Pages: 113-116
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.597.113
• Online since: July 2014
• Authors: Yue Qin Wang*, Juan Gao, Shao Ping Yan
• Keywords: Electron-Phonon Coupling, First-Principle, OsB₂, Superconductivity

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