Third-order guided-wave distributed Bragg reflectors fabricated by ion-exchange in KTiOPO/sub 4/

Abstract
Efficient, guided-wave distributed Bragg reflectors were fabricated in potassium titanyl phosphate (KTiOPO/sub 4/, KTP) by ion-exchange. The period of these gratings (0.7 /spl mu/m) was chosen to provide third-order Bragg reflection of the TM/sub 00/ mode at 860 nm. Gratings as short as 500 /spl mu/m provided nearly 100% reflectivity. The reflection from an ion-exchanged grating was used to provide the feedback required for operation of an extended-cavity GaAlAs diode laser. Gratings as short as 70 /spl mu/m provided adequate feedback for stable operation of the extended-cavity laser.