title: Modulation of electrical potential and conductivity in an atomic-layer semiconductor heterojunction.
abstract: Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport.
authors: Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
authors: Yu
authors: Y
authors: Kobayashi
authors: Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors: Shoji
authors: S
authors: Yoshida
authors: Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors: Ryuji
authors: R
authors: Sakurada
authors: Department of Electrical Engineering, Graduate School of Engineering, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.
authors: Kengo
authors: K
authors: Takashima
authors: Department of Electrical Engineering, Graduate School of Engineering, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.|Department of Liberal Arts, Faculty of Engineering, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.
authors: Takahiro
authors: T
authors: Yamamoto
authors: Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
authors: Tetsuki
authors: T
authors: Saito
authors: Research Institute for Science and Technology, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.
authors: Satoru
authors: S
authors: Konabe
authors: National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
authors: Takashi
authors: T
authors: Taniguchi
authors: National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
authors: Kenji
authors: K
authors: Watanabe
authors: Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
authors: Yutaka
authors: Y
authors: Maniwa
authors: Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors: Osamu
authors: O
authors: Takeuchi
authors: Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors: Hidemi
authors: H
authors: Shigekawa
authors: Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.|JST-PRESTO, Kawaguchi, Saitama 332-0012, Japan.
authors: Yasumitsu
authors: Y
authors: Miyata