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Femtosecond-Laser-Pulse Characterization and Optimization for CARS Microscopy.

ABSTRACT: We present a simple method and its experimental implementation to determine the pulse durations and linear chirps of the pump-and-probe pulse and the Stokes pulse in a coherent anti-Stokes Raman scattering microscope at sample level without additional autocorrelators. Our approach exploits the delay line, ubiquitous in such microscopes, to perform a convolution of the pump-and-probe and Stokes pulses as a function of their relative delay and it is based on the detection of the photons emitted from an appropriate non-linear sample. The analysis of the non-resonant four-wave-mixing and sum-frequency-generation signals allows for the direct retrieval of the pulse duration on the sample and the linear chirp of each pulse. This knowledge is crucial in maximizing the spectral-resolution and contrast in CARS imaging.

SUBMITTER: Piazza V

PROVIDER: S-EPMC4880195 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Femtosecond-Laser-Pulse Characterization and Optimization for CARS Microscopy.

Piazza Vincenzo V de Vito Giuseppe G Farrokhtakin Elmira E Ciofani Gianni G Mattoli Virgilio V

PloS one 20160525 5

We present a simple method and its experimental implementation to determine the pulse durations and linear chirps of the pump-and-probe pulse and the Stokes pulse in a coherent anti-Stokes Raman scattering microscope at sample level without additional autocorrelators. Our approach exploits the delay line, ubiquitous in such microscopes, to perform a convolution of the pump-and-probe and Stokes pulses as a function of their relative delay and it is based on the detection of the photons emitted fr ...[more]

PMID: 27224203

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