title: Dynamic Control of Optical Response in Layered Metal Chalcogenide Nanoplates.
abstract: Tunable optical transitions in ultrathin layered 2-dimensional (2D) materials unveil the electronic structures of materials and provide exciting prospects for potential applications in optics and photonics. Here, we present our realization of dynamic optical modulation of layered metal chalcogenide nanoplates using ionic liquid (IL) gating over a wide spectral range. The IL gating significantly increased the tuning range of the Fermi level and, as a result, substantially altered the optical transitions in the nanoplates. Using heavily n-doped Bi2Se3 nanoplates, we substantially modulated the light transmission through the ultrathin layer. A tunable, high-transmission spectral window in the visible to near-infrared region has been observed due to simultaneous shifts of both the plasma edge and absorption edge of the material. On the other hand, optical response of multilayer MoSe2 flakes gated by IL has shown enhanced transmission in both positive and negative biases, which is consistent with their ambipolar electrical behavior. The electrically controlled optical property tuning in metal chalcogenide material systems provides new opportunities for potential applications, such as wide spectral range optical modulators, optical filters, and electrically controlled smart windows with extremely low material consumption.
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Kyle
authors.initials: K
authors.lastname: Tom
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Chunming
authors.initials: C
authors.lastname: Huang
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.|Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Yuan
authors.forename: Hong
authors.initials: H
authors.lastname: Ding
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Changhyun
authors.initials: C
authors.lastname: Ko
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Joonki
authors.initials: J
authors.lastname: Suh
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Pan
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Kristin A
authors.initials: KA
authors.lastname: Persson
authors.affiliation: Department of Materials Science and Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Yao
mesh_terms: D001729:Bismuth / Q000737:chemistry; D018011:Chalcogens / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D008027:Light; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology; D055095:Optics and Photonics / Q000379:methods*; D012643:Selenium / Q000737:chemistry
chemical_list: D018011:Chalcogens; D052578:Ionic Liquids; D012643:Selenium; D001729:Bismuth
keywords: 2D materials; Dynamic optical tuning; ionic liquid gating; metal chalcogenides