Laser-induced thermal grating spectroscopy based on femtosecond laser multi-photon absorption
Laser-induced grating spectroscopy (LIGS) is for the first time explored in a configuration based on the crossing of two focused femtosecond (fs) laser pulses (800-nm wavelength) and a focused continuous-wave (cw) laser beam (532-nm wavelength). A thermal grating was formed by multi-photon absorption of the fs-laser pulses by N 2 with a pulse energy around 700 μ J (∼ 45 TW/cm 2). The feasibility o
