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arXiv · 1512.04461

Broadband Femtosecond Transient Absorption Spectroscopy for CVD MoS2 monolayer

Shrouq H. Aleithan·Maksim Y. Livshits·Sudiksha Khadka·Jeffrey J. Rack·Martin Kordesch·Eric Stinaff
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Abstract

Carrier dynamics in monolayer MoS2 have been investigated using broadband femtosecond transient absorption spectroscopy (FTAS). A tunable pump pulse was used while a broadband probe pulse revealed ground and excited state carrier dynamics. Interestingly, for pump wavelengths both resonant and non-resonant with the A and B excitons, we observe a broad ground state bleach around 2.9 eV, with decay components similar to A and B. Associating this bleach with the band nesting region between K and Gamma in the band structure indicates significant k-space delocalization and overlap among excitonic wave functions identified as A, B, C, and D. Comparison of time dynamics for all features in resonance and non-resonance excitation is consistent with this finding.

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Shrouq H. Aleithan, Maksim Y. Livshits, Sudiksha Khadka, Jeffrey J. Rack, Martin Kordesch, Eric Stinaff. 2016-06-21. Broadband Femtosecond Transient Absorption Spectroscopy for CVD MoS2 monolayer. https://doi.org/10.1103/physrevb.94.035445

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