Laser-Beam-Patterned Topological Insulating States on Thin Semiconducting MoS_{2}

H Mine; A Kobayashi; T Nakamura; T Inoue; S Pakdel; D Marian; E Gonzalez-Marin; S Maruyama; S Katsumoto; A Fortunelli; J J Palacios; J Haruyama

doi:10.1103/PhysRevLett.123.146803

Laser-Beam-Patterned Topological Insulating States on Thin Semiconducting MoS_{2}

Phys Rev Lett. 2019 Oct 4;123(14):146803. doi: 10.1103/PhysRevLett.123.146803.

Authors

H Mine¹, A Kobayashi¹, T Nakamura², T Inoue³, S Pakdel^{4

5

6}, D Marian⁷, E Gonzalez-Marin⁷, S Maruyama³, S Katsumoto², A Fortunelli⁸, J J Palacios^{9

4}, J Haruyama^{1

2}

Affiliations

¹ Faculty of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Sagamihara, Kanagawa 252-5258, Japan.
² Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan.
³ Department of Mechanical Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
⁴ Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera (INC), and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
⁵ School of Electrical and Computer Engineering, University College of Engineering, University of Tehran, Tehran 14395-515, Iran.
⁶ Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
⁷ Dipartimento di Ingegneria dell'Informazione, Università di Pisa, Pisa 56122, Italy.
⁸ CNR, National Research Council, Pisa 56124, Italy.
⁹ Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA.

PMID: 31702203
DOI: 10.1103/PhysRevLett.123.146803

Abstract

Identifying the two-dimensional (2D) topological insulating (TI) state in new materials and its control are crucial aspects towards the development of voltage-controlled spintronic devices with low-power dissipation. Members of the 2D transition metal dichalcogenides have been recently predicted and experimentally reported as a new class of 2D TI materials, but in most cases edge conduction seems fragile and limited to the monolayer phase fabricated on specified substrates. Here, we realize the controlled patterning of the 1T^{'} phase embedded into the 2H phase of thin semiconducting molybdenum-disulfide by laser beam irradiation. Integer fractions of the quantum of resistance, the dependence on laser-irradiation conditions, magnetic field, and temperature, as well as the bulk gap observation by scanning tunneling spectroscopy and theoretical calculations indicate the presence of the quantum spin Hall phase in our patterned 1T^{'} phases.