Second harmonic generation tuning curves in quasiphase-matched potassium titanyl phosphate with narrow, high-intensity beams.

The second harmonic generation (SHG) tuning curves with temperature and angle of incidence were measured in periodically poled KTiOPO[sub 4] for narrow fundamental beams at intensities typical of quadratic soliton generation. Mutual self-focusing of the fundamental and harmonic, cascading, and walk-off for light incidence away from the poling axis drastically distorted the SHG response curves, in good agreement with theory. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]