Ab initio investigation of superconductivity in noncentrosymmetric Ca3Ir4Ge4

作者：Tutuncu H M^*; Srivastava G P

来源：Philosophical Magazine, 2015, 95(20): 2228-2239.

DOI：10.1080/14786435.2015.1057256

• lattice dynamics
• electronic properties
• density-functional theory
• superconductivity
• vibrational properties
• phonons

Ab initio pseuduopotential calculations are made to investigate structural, electronic, vibrational and superconducting properties of the recently discovered noncentrosymmetric
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. Even without the inclusion of the spin-orbit interaction, this material is found to be a BCS superconductor, with a medium strength average electron-phonon coupling parameter
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. The largest contribution (
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94%) to this parameter comes from the interaction of electrons near the Fermi level from Ir 6p, Ge 4p and Ca 3d states with the acoustic and optical phonon modes up to 5.8THz. With an acceptable choice
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for effective screened Coulomb repulsion parameter, the superconducting transition temperature
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K is obtained, in good agreement with a recent experimental study.

• 出版日期2015-7-13