title: 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.
authors.affiliation: Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, I-56127 Pisa, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Piazza
authors.affiliation: Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, I-56127 Pisa, Italy.|NEST, Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: de Vito
authors.affiliation: Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @SSSA, Viale RinaldoPiaggio 34, I-56025 Pontedera, Pisa, Italy.
authors.forename: Elmira
authors.initials: E
authors.lastname: Farrokhtakin
authors.affiliation: Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @SSSA, Viale RinaldoPiaggio 34, I-56025 Pontedera, Pisa, Italy.|Polytechnic University of Torino, Department of Aerospace and Mechanical Engineering, Corso Duca degli Abruzzi 24, I-10129 Torino, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Ciofani
authors.affiliation: Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @SSSA, Viale RinaldoPiaggio 34, I-56025 Pontedera, Pisa, Italy.
authors.forename: Virgilio
authors.initials: V
authors.lastname: Mattoli
mesh_terms: D004867:Equipment Design; D007089:Image Enhancement / Q000379:methods; D007834:Lasers; D008853:Microscopy / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*