title: Ionic Liquid Gating of Suspended MoS2 Field Effect Transistor Devices.
abstract: We demonstrate ionic liquid (IL) gating of suspended few-layer MoS2 transistors, where ions can accumulate on both exposed surfaces. Upon application of IL, all free-standing samples consistently display more significant improvement in conductance than substrate-supported devices. The measured IL gate coupling efficiency is up to 4.6 × 10(13) cm(-2) V(-1). Electrical transport data reveal contact-dominated electrical transport properties and the Schottky emission as the underlying mechanism. By modulating IL gate voltage, the suspended MoS2 devices display metal-insulator transition. Our results demonstrate that more efficient charge induction can be achieved in suspended two-dimensional (2D) materials, which with further optimization, may enable extremely high charge density and novel phase transition.
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Fenglin
authors.initials: F
authors.lastname: Wang
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Petr
authors.initials: P
authors.lastname: Stepanov
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Mason
authors.initials: M
authors.lastname: Gray
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Chun Ning
authors.initials: CN
authors.lastname: Lau
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Mikhail E
authors.initials: ME
authors.lastname: Itkis
authors.affiliation: †Department of Physics and Astronomy, ‡Department of Chemistry, and §Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California 92521, United States.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Haddon
keywords: Ionic liquid gating; metal−insulator transition; molybdenum disulfide; suspended structure