Fluorescence-Detected Pump–Probe Spectroscopy for Artifact-Free Detection of Stokes Shift Dynamics
Year: 2025
Type: article
Abstract: Fluorescence-detected pump-probe (F-PP) spectroscopy is a recently developed method to study excited-state dynamics. F-PP combines the temporal resolution of conventional transient absorption (TA) spectroscopy with the sensitivity of fluorescence detection. In this work, we demonstrate inherently phase-stable F-PP spectroscopy using 20 fs pulses to monitor the ultrafast Stokes shift dynamics of a solvated fluorophore (Y12). We observed a shift in the stimulated emission maximum with a time constant of 84 fs. In contrast to TA, F-PP provides a coherent artifact-free view of this process. Using quantitative signal background subtraction, as discussed in this work, F-PP uncovers the pure stimulated emission spectrum and its ultrafast dynamics. This signal isolation is a clear advantage over TA, where different contributions often overlap heavily. We compare results from F-PP and TA on an equal footing using the same excitation pulses, emphasizing the features and advantages of the F-PP technique.
Institutions: Technical University of Munich, Charles University
Language: English
Subfield: Physical and Theoretical Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
OpenAlex ID: W4410243114