@article{ce4ba3a70a164d6ca1a348cd85c87b30,
title = "Imaging of pure spin-valley diffusion current in WS2-WSe2 heterostructures",
abstract = "Transition metal dichalcogenide (TMDC) materials are promising for spintronic and valleytronic applications because valley-polarized excitations can be generated and manipulated with circularly polarized photons and the valley and spin degrees of freedom are locked by strong spin-orbital interactions. In this study we demonstrate efficient generation of a pure and locked spin-valley diffusion current in tungsten disulfide (WS2)–tungsten diselenide (WSe2) heterostructures without any driving electric field. We imaged the propagation of valley current in real time and space by pump-probe spectroscopy. The valley current in the heterostructures can live for more than 20 microseconds and propagate over 20 micrometers; both the lifetime and the diffusion length can be controlled through electrostatic gating. The high-efficiency and electric-field–free generation of a locked spin-valley current in TMDC heterostructures holds promise for applications in spin and valley devices.",
author = "Chenhao Jin and Jonghwan Kim and {Iqbal Bakti Utama}, M. and Regan, {Emma C.} and Hans Kleemann and Hui Cai and Yuxia Shen and Shinner, {Matthew James} and Arjun Sengupta and Kenji Watanabe and Takashi Taniguchi and Sefaattin Tongay and Alex Zettl and Feng Wang",
note = "Funding Information: This work was supported primarily by the director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division of the U.S. Department of Energy, under contract no. DE-AC02-05-CH11231 (van der Waals heterostructures program, KCWF16). The device fabrication was supported by the NSF EFRI program (EFMA-1542741). The growth of hBN crystals was supported by the Elemental Strategy Initiative conducted by the MEXT, Japan, and JSPS KAKENHI grant JP15K21722. S.T. acknowledges support from NSF DMR CAREER award 1552220 for the growth of MoS2 and WSe2 crystals. H.K. acknowledges fellowship support from the Deutsche Forschungsgemeinschaft (KL 2961/1-1). Publisher Copyright: {\textcopyright} 2017 The Authors.",
year = "2018",
month = may,
day = "25",
doi = "10.1126/science.aao3503",
language = "English (US)",
volume = "360",
pages = "893--896",
journal = "Science",
issn = "0036-8075",
publisher = "American Association for the Advancement of Science",
number = "6391",
}