In monolayer semiconductor transition metal dichalcogenides, the exciton-phonon interaction is expected to strongly affect the photocarrier dynamics. Here, we report on an unusual oscillatory enhancement of the neutral exciton photoluminescence with the excitation laser frequency in monolayer MoSe2. The frequency of oscillation matches that of the M-point longitudinal acoustic phonon, LA(M). Oscillatory behavior is also observed in the steady-state emission linewidth and in timeresolved photoluminescence excitation data, which reveals variation with excitation energy in the exciton lifetime. These results clearly expose the key role played by phonons in the exciton formation and relaxation dynamics of two-dimensional van der Waals semiconductors.
@article{arxiv.1701.02770,
title = {Phonon-assisted oscillatory exciton dynamics in monolayer MoSe2},
author = {Colin M. Chow and Hongyi Yu and Aaron M. Jones and John R. Schaibley and Michael Koehler and David G. Mandrus and R. Merlin and Wang Yao and Xiaodong Xu},
journal= {arXiv preprint arXiv:1701.02770},
year = {2017}
}
Comments
Published in npj 2D Materials and Applications. https://www.nature.com/articles/s41699-017-0035-1