The electronic structure, lattice dynamics, and electron-phonon coupling of gallium-doped germanium are investigated using a initio supercell methods. Our results indicate the superconducting transition in gallium-doped germanium can be explained within a standard phonon mediated mechanism. The contribution of acoustic modes to the coupling constant λ almost entirely comes from Ga related modes, and ~25% to λ. The calculated coupling constant is 0.35 and the corresponding transition temperature is 0.44 K for the gallium-doped germanium with 6.25% gallium content using Coulomb pseudopotential μ*=0.1, in agreement well with the experimental data.
The electronic structure, lattice dynamics, and electron-phonon coupling of gallium-doped germanium are investigated using a initio supercell methods. Our results indicate the superconducting transition in gallium-doped germanium can be explained within a standard phonon mediated mechanism. The contribution of acoustic modes to the coupling constant λ almost entirely comes from Ga related modes, and ~25% to λ. The calculated coupling constant is 0.35 and the corresponding transition temperature is 0.44 K for the gallium-doped germanium with 6.25% gallium content using Coulomb pseudopotential μ*=0.1, in agreement well with the experimental data.
DAI Jun;LI Zhen-Yu;YANG Jin-Long. Electron-phonon Coupling in Gallium-Doped Germanium[J]. 中国物理快报, 2010, 27(8): 86102-086102.
DAI Jun, LI Zhen-Yu, YANG Jin-Long. Electron-phonon Coupling in Gallium-Doped Germanium. Chin. Phys. Lett., 2010, 27(8): 86102-086102.
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