Fabrication of periodic domain grating in LiNbO3 by electron beam writing for application of nonlinear optical processes

A novel technique for the fabrication of domain reversed gratings in LiNbO₃ by means of direct electron beam writing at room temperature without any static bias is reported. The domain grating has been achieved not only at the -c surface of the crystal, but also for the entire region of the crystal. Such a structure should be useful for various nonlinear optic applications. A preliminary study on the second harmonic generation has also been demonstrated under the quasi-phase matched condition with high efficiency.