Coupled exciton-trion spin dynamics in a MoSe 2 monolayer
Source abstract
Abstract
Abstract Understanding and controlling the spin degree of freedom in two-dimensional transition metal dichalcogenides offers the potential for designing functional quantum materials. This work investigates the dynamics of photo- and resident carrier spins in an encapsulated MoSe 2 monolayer using non-degenerate time-resolved Kerr-rotation microscopy. The lightly doped monolayer exhibits clear exciton and trion resonances with spin-polarizations that are characterized by a fast (~20 ps) decay attributed to photocarrier relaxation and recombination, followed by a slow (~690 ps) decay associated with resident carrier depolarization. Dual-frequency Kerr-rotation spectra directly reveal exciton-trion coupling on ultrashort timescales and within the spin coherence time of the system. Moreover, the distribution of the exciton-trion coupling features exposes inhomogeneous broadening likely arising from different domains within the excitation spot.
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Research context
OpenAlex topics: 2D Materials and Applications · Perovskite Materials and Applications · Quantum Dots Synthesis And Properties
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Affiliations
Technische Universität Dortmund
The authors have contributed equally to the paper.
West Virginia University
Funding
Deutsche Forschungsgemeinschaft
References (31)
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