Fluorescence-free super-resolution imaging and nano-environment sensing by assessing temporal evolutions of optical processes

This presentation will center on the investigation of two distinct relaxation mechanisms: photothermal relaxation and vibrational dephasing. We introduce a fluorescence-independent super-resolution technique, photothermal relaxation localization (PEARL) microscopy. PEARL microscopy leverages the evaluation of absorption-induced local refractive index modulation to extract intricate spatial details. Notably, PEARL is universally applicable to a broad range of absorbers across various spectral windows, encompassing both vibrational and electronic absorptions. Additionally, we employ a femtosecond Time-Resolved Coherent Anti-Stokes Raman Scattering (T-CARS) to scrutinize the temporal characteristics of molecular vibrations. Our findings reveal vibrational dephasing as an emerging indicator capable of discerning subtle alterations in molecular structure and dynamics. This dual approach of extracting temporal features from diverse optical processes opens new vistas for detection and sensing across an array of scientific domains.