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arXiv · 2406.04454

Ultrafast Optical Control of Rashba Interactions in a TMDC Heterostructure

Henry Mittenzwey·Abhijeet Kumar·Raghav Dhingra·Kenji Watanabe·Takashi Taniguchi·Cornelius Gahl·Kirill I. Bolotin·Malte Selig·Andreas Knorr
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Abstract

We investigate spin relaxation dynamics of interlayer excitons in a MoSe2/MoS2 heterostructure induced by the Rashba effect. In such a system, Rashba interactions arise from an out-of-plane electric field due to photo-generated interlayer excitons inducing a phonon-assisted intravalley spin relaxation. We develop a theoretical description based on a microscopic approach to quantify the magnitude of Rashba interactions and test these predictions via time-resolved Kerr rotation measurements. In agreement with the calculations, we find that the Rashba-induced intravalley spin mixing becomes the dominating spin relaxation channel above T = 50 K. Our work identifies a previously unexplored spin-depolarization channel in heterostructures which can be used for ultrafast spin manipulation.

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Henry Mittenzwey, Abhijeet Kumar, Raghav Dhingra, Kenji Watanabe, Takashi Taniguchi, Cornelius Gahl, Kirill I. Bolotin, Malte Selig, Andreas Knorr. 2024-06-06. Ultrafast Optical Control of Rashba Interactions in a TMDC Heterostructure. https://arxiv.org/abs/2406.04454

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