Spectral broadening of sub-μJ Ytterbium laser pulses in cadmium sulfide crystal with subsequent filtering by frequency doubling

We experimentally report on the spectral broadening of lasers pulses from an Ytterbium (Yb) laser with 0.8μJ energy level via self-phase modulation in cadmium sulfide (CdS) semiconductor crystal. Then, by frequency doubling the pulse into a beta barium borate crystal (BBO), the spatial beam profile is cleaned out while maintaining the bandwidth enhancement. At the end, the laser pulse, around 512 nm, is compressed up to 45 fs using two standard transmissive grating resulting in a pulse compression factor of 6.13.