Gate-tunable linear magnetoresistance in molybdenum disulfide field-effect transistors with graphene insertion layer

Molybdenum disulfide (MoS₂) holds great promise as atomically thin two-dimensional (2D) semiconductor for future electronics and opto-electronics. In this report, we study the magnetoresistance (MR) of MoS₂ field-effect transistors (FETs) with graphene insertion layer at the contact interface. Owing to the unique device structure and high-quality contact interface, a gate-tunable linear MR up to 67% is observed at 2 K. By comparing with the MRs of graphene FETs and MoS₂ FETs with conventional metal contact, it is found that this unusual MR is most likely to be originated from the contact interfaces between graphene and MoS₂, and can be explained by the classical linear MR model caused by spatial fluctuation of carrier mobility. Our study demonstrates large MR responses in MoS₂-based systems through heterojunction design, shedding lights for the future magneto-electronics and van der Waals heterostructures.