Samenvatting
Semiconductor transition metal dichalcogenides (TMDs) have equivalent dynamics for their two spin/valley species. This arises from their energy-degenerated spin states, connected via time-reversal symmetry. When an out-of-plane magnetic field is applied, time-reversal symmetry is broken and the energies of the spin-polarized bands shift, resulting in different bandgaps and dynamics in the K + and K − valleys. Here, we use time-resolved Kerr rotation to study the magnetic field dependence of the spin dynamics in monolayer MoSe2. We show that the magnetic field can control the light-induced spin accumulation of the two valley states, with a small effect on the recombination lifetimes. We unveil that the magnetic field-dependent spin accumulation is in agreement with hole spin dynamics at the longer timescales, indicating that the electron spins have faster relaxation rates. We propose a rate equation model that suggests that lifting the energy-degeneracy of the valleys induces an ultrafast spin-flip toward the stabilization of the valley with the higher valence band energy. Our results provide an experimental insight into the ultrafast charge and spin dynamics in TMDs and a way to control it, which will be useful for the development of new spintronic and valleytronic applications.
Originele taal-2 | English |
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Artikelnummer | 035013 |
Aantal pagina's | 7 |
Tijdschrift | 2D Materials |
Volume | 10 |
Nummer van het tijdschrift | 3 |
Vroegere onlinedatum | 28-feb.-2023 |
DOI's | |
Status | Published - jul.-2023 |
Vingerafdruk
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Experimental data for "Magnetic field control of light-induced spin accumulation in monolayer MoSe2"
Rojas-Lopez, R. R. (Contributor), Hendriks, F. (Contributor), van der Wal, C. H. (Contributor), Guimarães, P. S. S. (Contributor) & Guimarães, M. H. D. (Contributor), ZENODO, 16-apr.-2023
Dataset