Cascaded second-harmonic and sum-frequency generation of a CO/sub 2/ laser using a single quasi-phase-matched GaAs crystal

Summary form only given. In the present paper we report the third-harmonic generation (THG) of CO/sub 2/ pulsed and continuous lasers at 10.6 /spl mu/m thanks to cascaded second-harmonic and sum-frequency generation (SHG and SFG). We used commercial [110] semi-insulating undoped GaAs wafers, of 106-/spl mu/m thickness for the SHG section and 89-/spl mu/m thickness for the SFG section.