Electron-Phonon Coupling in Boron-Doped Diamond Superconductor

TL;DR

This study uses density functional calculations to analyze electron-phonon interactions in boron-doped diamond, confirming its phonon-mediated superconductivity and accurately estimating its transition temperature.

Contribution

The paper provides a detailed first-principles analysis of electron-phonon coupling in boron-doped diamond, with improved calculations of the coupling constant and transition temperature.

Findings

Electron-phonon coupling constant is 0.39.

Superconducting transition temperature is estimated at 4.4 K.

Optical phonon modes involving B vibrations are crucial.

Abstract

The electronic structure, lattice dynamics, and electron-phonon coupling of the boron-doped diamond are investigated using the density functional supercell method. Our results indicate the boron-doped diamond is a phonon mediated superconductor, con rming previous theoretical conclusions deduced from the calculations employing the virtual crystal approximation. We show that the optical phonon modes involving B vibrations play an important role in the electron-phonon coupling. Di erent from previous theoretical results, our calculated electron-phonon coupling constant is 0.39 and the estimated superconducting transition temperature Tc is 4.4 K for the boron doped diamond with 2.78% boron content using the Coulomb pseudopotential \mu*= 0.10, in excellent agreement with the experimental result.