Generation of Femtosecond Laser Pulses Tunable from 380 nm to 465 nm via Cascaded Nonlinear Optical Mixing in a Noncollinear Optical Parametric Amplifier with a Type-I Phase Matched BBO Crystal

[[abstract]]We report the generation of tunable femtosecond pulses from 380nm to 465nm near the degenerate point of a 405-nm pumped type-I BBO noncollinearly phase-matched optical parametric amplifier (NOPA). The tunable UV/blue radiation is obtained from sum frequency generation (SFG) between the OPA output and the residual fundamental beam at 810-nm and cascaded second harmonic generation (SHG) of OPA. With a fixed seeding angle, the generated SFG and SHG covers from 385 nm to 465-nm. With a pumping energy of 75 muJ at 405 nm, the optical conversion efficiency from the pump to the tunable SFG is more than 5% and the efficiency of SHG of the OPA is about 2%[[fileno]]2010144010100[[department]]物理