- Main
Imaging of pure spin-valley diffusion current in WS2-WSe2 heterostructures.
- Author(s): Jin, Chenhao
- Kim, Jonghwan
- Utama, M Iqbal Bakti
- Regan, Emma C
- Kleemann, Hans
- Cai, Hui
- Shen, Yuxia
- Shinner, Matthew James
- Sengupta, Arjun
- Watanabe, Kenji
- Taniguchi, Takashi
- Tongay, Sefaattin
- Zettl, Alex
- Wang, Feng
- et al.
Published Web Location
https://doi.org/10.1126/science.aao3503Abstract
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.