Electron-phonon coupling and superconductivity in arsenic under pressure

Article

关键词: STRUCTURAL PHASE-TRANSITION;    WANNIER FUNCTIONS;    TOTAL-ENERGY;    TEMPERATURE;    TRANSFORMATION;    STABILITY;    ELEMENTS;    LITHIUM;    STATE;    GAS;   

DOI  :  10.1103/PhysRevB.86.094515

来源: SCIE

【 摘 要 】

We perform first-principles calculations of the electronic structure, phonon dispersion, and electron-phonon coupling in elemental As at various pressures above and below the rhombohedral A7 to simple cubic (sc) structural transition. We find that the electron-phonon coupling constant lambda, and hence the superconducting transition temperature T-c, is largest near the structural transition and decreases away from it. Changes in lambda as a function of pressure are primarily explained by changes in the density of states at the Fermi level for pressures below the transition, and by changes in phonon frequency for pressures above the transition. Although the couplings to the Gamma(1) optical phonon mode (for A7) and the R phonon mode (for sc) are large, the contribution of these modes to lambda for their respective structures is modest.

【 授权许可】

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