Ultrafast traveling-wave electro-optic deflector using domain-engineered LiTaO3 crystal

Abstract

We report a traveling-wave electro-optic sinusoidal deflector which operates in a picosecond time scale. The deflector is fabricated by use of simple domain-engineering processes in a LiTaO3 electro-optic crystal. The shape of the domain inverted region in a traveling-wave electro-optic phase modulator is theoretically designed in consideration of velocity mismatch between an optical group velocity and a microwave phase velocity in a crystal for spatial linear distribution of the modulation index within an optical beam cross section. At a deflection period of 61.5 ps, the maximum resolvable spot number of 13.0±0.6 is demonstrated. Our EOD can be applicable to time-space optical information processing systems with the minimum temporal resolution of 1.5 ps.