title: The electronic structure of quasi-free-standing germanene on monolayer MX (M = Ga, In; X = S, Se, Te).
abstract: For the first time by using the ab initio density functional theory, the stability and electronic structures of germanene on monolayer GaS, GaSe, GaTe and InSe have been investigated. Germanene preserves its buckled-honeycomb structure on all the studied substrates similar to the free-standing case. Moreover, germanene stays neutral and preserves its Dirac-cone-like band structure on monolayer GaTe and InSe. In these two cases, a bandgap of 0.14-0.16 eV opens at the Dirac point of germanene, while the effective masses remain as small as 0.05-0.06 times the free-electron mass. The estimated carrier mobility is up to 2.2 × 10(5) cm(2) V(-1) s(-1). These features show that monolayer GaTe and InSe are promising as substrates for germanene devices.
authors.affiliation: Department of Materials Engineering, The University of Tokyo, Tokyo 113-8656, Japan. zeyuan_ni@cello.t.u-tokyo.ac.jp watanabe@cello.t.u-tokyo.ac.jp.
authors.forename: Zeyuan
authors.initials: Z
authors.lastname: Ni
authors.forename: Emi
authors.initials: E
authors.lastname: Minamitani
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Ando
authors.forename: Satoshi
authors.initials: S
authors.lastname: Watanabe