Rovibrational hybrid fs/ps CARS using a volume Bragg grating for N_2 thermometry

Abstract

Coherent anti-Stokes Raman scattering (CARS) spectra of N2 in the hybrid femtosecond/picosecond regime have been recorded with 0.7 cm(-1) resolution. The Q-branch rovibrational structure has been resolved, making it suitable for gas-phase simultaneous rotational and vibrational thermometry applications. Resolving this spectral structure requires synchronization of a narrowband picosecond probe pulse with a broadband femtosecond pair of pump and Stokes pulses. It is achieved using a single femtosecond ytterbium-laser source and a volume Bragg grating in a compact experimental arrangement.