LAUSR

We experimentally demonstrate an efficient broadband second-harmonic generation (SHG) process with a tunable mode-locked Ti:sapphire oscillator. We have achieved a robust broadband and efficient flat conversion of more than 35 nm wavelength by designing an adiabatic aperiodically poled potassium titanyl phosphate crystal. Moreover, we have shown that with such efficient flat conversion, we can shape and control broadband second-harmonic pulses. More specifically, we assign a spectral phase of absolute value and π-step, which allows wavelength tunable intense pump-probe and amplitude modulation of the broadband second-harmonic output. Such spectral phases serve as a proof of concept for other pulse-shaping applications for nonlinear spectroscopy and imaging.