14 November 2003 Polarized stimulated emission depletion studies of two-photon excited states
Author Affiliations +
Stimulated emission depletion (STED) population and polarisation dynamics following two-photon excitation are investigated for rhodamine 6G in ethylene glycol. Time resolved fluorescence intensity and polarisation measurements were made using picosecond time-correlated single photon counting (TCSPC). Cross-sections for the stimulated transition were measured between 614nm (2.32x10-16 cm2) and 663.5nm (6.05x10-17 cm2), ground state vibrational lifetimes were found to vary between 314fs and 467fs. A collinear (180°) excitation-detection geometry was employed to investigate re-polarisation of the excited state array yielding fluorescence anisotropies above the two-photon limit. The circumvention of single-photon selection rules is demonstrated allowing the measurement of higher order parameters and correlation functions that are wholly inaccessible to 'conventional' (spontaneous) time resolved fluorescence techniques.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Daven A. Armoogum, Daven A. Armoogum, Richard J. Marsh, Richard J. Marsh, Angus J. Bain, Angus J. Bain, } "Polarized stimulated emission depletion studies of two-photon excited states", Proc. SPIE 5222, Nanocrystals, and Organic and Hybrid Nanomaterials, (14 November 2003); doi: 10.1117/12.505839; https://doi.org/10.1117/12.505839

Back to Top