@article{ebaff7bfadb141faa9c482d813c82c71,
title = "Polariton Transitions in Femtosecond Transient Absorption Studies of Ultrastrong Light-Molecule Coupling",
abstract = "Strong light-matter coupling is emerging as a fascinating way to tune optical properties and modify the photophysics of molecular systems. In this work, we studied a molecular chromophore under strong coupling with the optical mode of a Fabry-Perot cavity resonant to the first electronic absorption band. Using femtosecond pump-probe spectroscopy, we investigated the transient response of the cavity-coupled molecules upon photoexcitation resonant to the upper and lower polaritons. We identified an excited state absorption from upper and lower polaritons to a state at the energy of the second cavity mode. Quantum mechanical calculations of the many-molecule energy structure of cavity polaritons suggest assignment of this state as a two-particle polaritonic state with optically allowed transitions from the upper and lower polaritons. We provide new physical insight into the role of two-particle polaritonic states in explaining transient signatures in hybrid light-matter coupling systems consistent with analogous many-body systems.",
author = "Delpo, {Courtney A.} and Bryan Kudisch and Park, {Kyu Hyung} and Khan, {Saeed Uz Zaman} and Francesca Fassioli and Daniele Fausti and Rand, {Barry P.} and Scholes, {Gregory D.}",
note = "Funding Information: This research was funded by the Gordon and Betty Moore Foundation through Grant GBMF7114. C.A.D. acknowledges acknowledge the use of Princeton{\textquoteright}s Imaging and Analysis Center, which is partially supported by the Princeton Center for Complex Materials, a National Science Foundation (NSF)-MRSEC program (DMR-1420541). B.K. acknowledges support by the National Science Foundation Graduate Research Fellowship under Grant DGE-1656466. S.U.Z.K. and B.P.R. acknowledge funding from the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-SC0012458. F.F. acknowledges financial support from the European Union{\textquoteright}s H2020 Marie Sk{\l}odowska Curie actions, Grant 799408. D.F. was supported by the European Commission through the European Research Council (ERC), Project INCEPT, Grant 677488. This research made use of the PRISM Cleanroom at Princeton University. Funding Information: This research was funded by the Gordon and Betty Moore Foundation through Grant GBMF7114. C.A.D. acknowledges acknowledge the use of Princeton?s Imaging and Analysis Center, which is partially supported by the Princeton Center for Complex Materials a National Science Foundation (NSF)-MRSEC program (DMR-1420541). B.K. acknowledges support by the National Science Foundation Graduate Research Fellowship under Grant DGE-1656466. S.U.Z.K. and B.P.R. acknowledge funding from the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-SC0012458. F.F. acknowledges financial support from the European Union?s H2020 Marie Sk?odowska Curie actions, Grant 799408. D.F. was supported by the European Commission through the European Research Council (ERC), Project INCEPT, Grant 677488. This research made use of the PRISM Cleanroom at Princeton University. Publisher Copyright: Copyright {\textcopyright} 2020 American Chemical Society.",
year = "2020",
month = apr,
day = "2",
doi = "10.1021/acs.jpclett.0c00247",
language = "English (US)",
volume = "11",
pages = "2667--2674",
journal = "Journal of Physical Chemistry Letters",
issn = "1948-7185",
publisher = "American Chemical Society",
number = "7",
}