title: β-tin→Imma→sh phase transitions of germanium.
abstract: New paths were designed for the investigations of the β-tin→Imma→sh phase transitions in nanocrystalline Ge under conditions of hydrostatic stress. A second-order transition between the β-tin and Imma phases was identified at 66 GPa, and a first-order transition between the Imma and sh phases was determined at 90 GPa. Superconductivity was obtained up to 190 GPa using the acquired structural data in first-principles calculations. This provides evidence that the standard electron-phonon coupling mechanism is responsible for superconductivity in Ge, as evidenced by the good agreement between the calculations and existing experiments.
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA.
authors.forename: Xiao-Jia
authors.initials: XJ
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.forename: Yue
authors.initials: Y
authors.lastname: Meng
authors.forename: Rui-Qin
authors.initials: RQ
authors.lastname: Zhang
authors.forename: Hai-Qing
authors.initials: HQ
authors.lastname: Lin
authors.forename: Viktor V
authors.initials: VV
authors.lastname: Struzhkin
authors.forename: Ho-kwang
authors.initials: HK
authors.lastname: Mao