title: Work Function Tuning in Two-Dimensional MoS2Field-Effect-Transistors with Graphene and Titanium Source-Drain Contacts.
abstract: Based on the first principles calculation, we investigate the electronic band structures of graphene-MoS2and Ti-MoS2heterojunctions under gate-voltages. By simultaneous control of external electric fields and carrier charging concentrations, we show that the graphene's Dirac point position inside the MoS2bandgap is easily modulated with respect to the co-varying Fermi level, while keeping the graphene's linear band structure around the Dirac point. The easy modulation of graphene bands is not confined to the special cases where the conduction-band-minimum point of MoS2and the Dirac point of graphene are matched up in reciprocal space, but is generalized to their dislocated cases. This flexibility caused by the strong decoupling between graphene and MoS2bands enhances the gate-controlled switching performance in MoS2-graphene hybrid stacking-device.
authors.affiliation: School of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, Korea.
authors.forename: Seung Su
authors.initials: SS
authors.lastname: Baik
authors.affiliation: Department of Physics and IPAP, Yonsei University, Seoul 03722, Korea.
authors.forename: Seongil
authors.initials: S
authors.lastname: Im
authors.affiliation: Department of Physics and IPAP, Yonsei University, Seoul 03722, Korea.|Center for Computational Studies of Advanced Electronic Material Properties, Yonsei University, Seoul 03722, Korea.
authors.forename: Hyoung Joon
authors.initials: HJ
authors.lastname: Choi