Chen P.-SFan S.-TLan H.-SCHEE-WEE LIU2021-09-022021-09-02201700223727https://www.scopus.com/inward/record.uri?eid=2-s2.0-85013354759&doi=10.1088%2f1361-6463%2f50%2f1%2f015107&partnerID=40&md5=37bdea02215bc4b43819193d6b1d941bhttps://scholars.lib.ntu.edu.tw/handle/123456789/580606The band structure of Ge in the lonsdaleite phase is calculated using first principles. Lonsdaleite Ge has a direct band gap at the Γ point. For the conduction band, the Γ valley is anisotropic with the low transverse effective mass on the hexagonal plane and the large longitudinal effective mass along the c axis. For the valence band, both heavy-hole and light-hole effective masses are anisotropic at the Γ point. The in-plane electron effective mass also becomes anisotropic under uniaxial tensile strain. The strain response of the heavy-hole mass is opposite to the light hole. ? 2016 IOP Publishing Ltd.Anisotropy; Calculations; Energy gap; Germanium; Strain; Band calculation; Effective mass; Electron effective mass; First principles; Hexagonal planes; Lonsdaleite; Strain response; Uniaxial tensile strain; Tensile strainjournal article10.1088/1361-6463/50/1/0151072-s2.0-85013354759