Pulse shaping and compression by second-harmonic generation with quasi-phase-matching gratings in the presence of arbitrary dispersion

A theoretical treatment of group-velocity dispersion and higher-order dispe rsion effects on the second-harmonic-generation (SHG) process with longitud inally nonuniform quasi-phase-matching (QPM) gratings is presented. We show how these dispersion terms can be accounted for in the design of a QPM-SHG pulse shaper. Our numerical simulation results show that, if the proper di spersion correction is included in the QPM grating design, one can generate sub-10-fs transform-limited pulses at 400 nm by doubling the output of a T i:sapphire oscillator. (C) 2000 Optical Society of America [S0740-3224(00)0 0808-0] OCIS codes: 140.7090, 190.7110, 190.2620, 190.4360, 230.4320, 320.5 520, 320.5540, 320.7110, 320.7080.