Ab initio prediction of superconductivity in molecular metallic hydrogen under high pressure

作者：Zhang, Lijun; Niu, Yingli; Li, Quan; Cui, Tian; Wang, Yi; Ma, Yanming^*; He, Zhi; Zou, Guangtian

来源：Solid State Communications, 2007, 141(11): 610-614.

DOI：10.1016/j.ssc.2006.12.029

• superconductors
• crystal structure and symmetry
• electron-phonon interactions
• phonons

We present a first ab initio investigation of the electron-phonon coupling (EPC) of molecular metallic hydrogen with a Cmca structure based on the linear-response approach. This molecular metallic hydrogen with overlapping bands has an elastic instability at lower pressures (<300 GPa), but stabilizes dynamically under further compression as indicated by the absence of phonon softening, thus supporting the choice of Cmca structure as a good candidate for metallic hydrogen. Within the conventional BCS theory, the predicted critical temperature T-c is 107 K at 347 GPa, so indicating good candidacy for a high temperature superconductor. With increasing pressure, interestingly, the EPC parameter lambda, hence, T-c increases, resulting from the increased electronic density of states at the Fermi level and EPC matrix element (l(2)), in spite of an enhanced average phonon frequency (a)2).

• 出版日期2007-3
• 单位吉林大学