Electro–optical tunable waveguide embedded multiscan Bragg gratings in lithium niobate by direct femtosecond laser writing

Kroesen S. , Horn W. , Imbrock J. , Denz C.

Abstract

We report on the monolithic integration of waveguide embedded, electro-optical tunable Bragg gratings in lithium niobate fabricated by direct femtosecond laser writing. The hybrid design that consists of a circular type-II waveguide and a multiscan type-I Bragg grating exhibits low loss ordinary and extraordinary polarized guiding as well as narrowband reflections in the c-band of optical communications. High bandwidth tunability of more than a peak width and nearly preserved electro-optic coefficients of r13 = 7.59pm V-1 and r33 = 23.21 pm V-1 are demonstrated.