Open AccessUltrafast background-free ro-vibrational fs/ps-CARS thermometry using an Yb:YAG crystal-fiber amplified probe
Author(s) -
Rosa Santagata,
Michael S. Scherman,
Mathieu Toubeix,
Malik Nafa,
Brigitte Trétout,
Alexandre Bresson
Publication year - 2019
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.032924
Subject(s) - optics , materials science , laser , femtosecond , raman scattering , ultrashort pulse , amplifier , fiber laser , coherent anti stokes raman spectroscopy , raman spectroscopy , optoelectronics , physics , cmos
A novel laser system for ro-vibrational spectroscopy using coherent anti-Stokes Raman Scattering in hybrid fs/ps regime is presented. A single Yb:KGW laser source is used as a master laser to generate the three CARS laser beams, namely the pump and Stokes femtosecond pulses and a 58 ps probe pulse. Master oscillator power amplifier (MOPA) architecture is implemented to increase the probe output power using a custom two stage free space linear amplifier. The probe is 0.37 cm -1 in width and 100 µJ in energy to allow resolving the Q-branch ro-vibrational lines of N 2 and recording single shot CARS spectra at kHz repetition rate in flames. An original and simple technique based on the study of the influence of probe delay and polarization has been setup to optimize nonresonant background rejection, with no loss in resonant contribution. CARS performances are reported for N 2 thermometry between 300 K and 3000 K, demonstrating state of the art precision.