Observation of 2D semiconductor P-type dark-exciton lifetime using two-photon ultrafast spectroscopy

Dmitry Panna, Krishna Balasubramanian*, Jayakrishna Khatei, Leonid Rybak, Yevgeny Slobodkin, Hadar Steinberg, Alex Hayat

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


We report direct measurements of intrinsic lifetimes of P-type dark-excitons in MoS2 monolayers. Using sub-gap excitation, we demonstrate two-photon excited direct population of P-type dark excitons, observe their scattering to bright states and decay with femtosecond resolution. In contrast to one-photon excitation schemes, non-monotonic density variation in bright exciton population observed under two-photon excitation shows the indirect nature of its population and competing decay pathways. Detailed modeling of different recombination pathways of bright and dark excitons allows experimental measurement of 2P dark → 1S bright exciton scattering rates. These insights into the dark states in a MoS2 monolayer pave the way for novel devices such as quantum memories and computing.

Original languageAmerican English
Pages (from-to)33427-33435
Number of pages9
JournalOptics Express
Issue number23
StatePublished - 2019

Bibliographical note

Publisher Copyright:
© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement


Dive into the research topics of 'Observation of 2D semiconductor P-type dark-exciton lifetime using two-photon ultrafast spectroscopy'. Together they form a unique fingerprint.

Cite this