title: Plasma-Wave Terahertz Detection Mediated by Topological Insulators Surface States.
abstract: Topological insulators (TIs) represent a novel quantum state of matter, characterized by edge or surface-states, showing up on the topological character of the bulk wave functions. Allowing electrons to move along their surface, but not through their inside, they emerged as an intriguing material platform for the exploration of exotic physical phenomena, somehow resembling the graphene Dirac-cone physics, as well as for exciting applications in optoelectronics, spintronics, nanoscience, low-power electronics, and quantum computing. Investigation of topological surface states (TSS) is conventionally hindered by the fact that in most of experimental conditions the TSS properties are mixed up with those of bulk-states. Here, we activate, probe, and exploit the collective electronic excitation of TSS in the Dirac cone. By engineering Bi2Te(3-x)Sex stoichiometry, and by gating the surface of nanoscale field-effect-transistors, exploiting thin flakes of Bi2Te2.2Se0.8 or Bi2Se3, we provide the first demonstration of room-temperature terahertz (THz) detection mediated by overdamped plasma-wave oscillations on the "activated" TSS of a Bi2Te2.2Se0.8 flake. The reported detection performances allow a realistic exploitation of TSS for large-area, fast imaging, promising superb impacts on THz photonics.
authors.affiliation: NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore , Piazza San Silvestro 12, Pisa I-56127, Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Viti
authors.affiliation: Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-University , Montpellier 2, Montpellier, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Coquillat
authors.affiliation: Università degli Studi della Calabria , Dipartimento di Fisica, via Ponte Bucci, 87036 Rende, Cosenza, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Politano
authors.affiliation: V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences , Koptyuga prospekt 3, Novosibirsk 630090, Russian Federation.
authors.forename: Konstantin A
authors.initials: KA
authors.lastname: Kokh
authors.affiliation: Institute of Catalisis and Inorganic Chemistry Department, Azerbaijan National Academy of Sciences , AZ-1143 Baku, Azerbaijan.|Institute of Physics, Azerbaijan National Academy of Science , AZ1143 Baku, Azerbaijan.
authors.forename: Ziya S
authors.initials: ZS
authors.lastname: Aliev
authors.affiliation: Institute of Catalisis and Inorganic Chemistry Department, Azerbaijan National Academy of Sciences , AZ-1143 Baku, Azerbaijan.
authors.forename: Mahammad B
authors.initials: MB
authors.lastname: Babanly
authors.affiliation: Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences , pr. Akademika Lavrent'eva 13, Novosibirsk 630090, Russian Federation.|Novosibirsk State University , ulica Pirogova 2, Novosibirsk 630090, Russian Federation.
authors.forename: Oleg E
authors.initials: OE
authors.lastname: Tereshchenko
authors.affiliation: Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-University , Montpellier 2, Montpellier, France.|Institute of High Pressure Institute Physics, Polish Academy of Sciences , 01-447 Warsaw, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Knap
authors.affiliation: Donostia International Physics Center (DIPC) , CFM-MPC, Centro Mixto CSIC-UPV/EHU, Departamento de Fisica de Materiales, UPV/EHU, E-20080 San Sebastian, Spain.|Tomsk State University , Prospekt Lenin 36, 634050 Tomsk, Russian Federation.|Saint Petersburg State University , Saint Petersburg 198504, Russian Federation.
authors.forename: Evgueni V
authors.initials: EV
authors.lastname: Chulkov
authors.affiliation: NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore , Piazza San Silvestro 12, Pisa I-56127, Italy.
authors.forename: Miriam S
authors.initials: MS
authors.lastname: Vitiello
keywords: graphene; plasma wave; terahertz; topological insulator