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DOE OSTI · 1601228

Time-Resolved Ultrafast Transient Polarization Spectroscopy to Investigate Nonlinear Processes and Dynamics in Electronically Excited Molecules on the Femtosecond Time Scale

Thurston, Richard·Brister, Matthew M.·Belkacem, Ali·Weber, Thorsten·Shivaram, Niranjan·Slaughter, Daniel S.
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Abstract

Here, we report a novel experimental technique to investigate ultrafast dynamics in photoexcited molecules by probing the third-order nonlinear optical susceptibility. A non-colinear 3-pulse scheme is developed to probe the ultrafast dynamics of excited electronic states using the optical Kerr effect by time-resolved polarization spectroscopy. Optical heterodyne and optical homodyne detection are demonstrated to measure the third-order nonlinear optical response for the S 1 excited state of liquid nitrobenzene, which is populated by 2-photon absorption of a 780 nm 35 fs excitation pulse.

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BibTeXRIS

Thurston, Richard, Brister, Matthew M., Belkacem, Ali, Weber, Thorsten, Shivaram, Niranjan, Slaughter, Daniel S.. 2020-05-04. Time-Resolved Ultrafast Transient Polarization Spectroscopy to Investigate Nonlinear Processes and Dynamics in Electronically Excited Molecules on the Femtosecond Time Scale. https://doi.org/10.1063/1.5144482

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