Secondhyphen;harmonic generation in a waveguide with domainhyphen;inverted regions like periodic lens sequence onzhyphen;face KTiOPO4crystal

摘要

A domain‐inverted waveguide with refractive‐index distribution of a periodic lens sequence instead of a conventional square shape was fabricated in az‐cut KTiOPO4(KTP) crystal. In the periodic lens sequence waveguide, the propagated laser beam through the waveguide was collimated and focused into a spot with a minimum amount of dispersion. The reason for the phenomenon of this periodic lens sequence waveguide structure can be explained from the viewpoint of ray matrix approximation.