“…As one kind of multifunctional optical crystal with great research value, LiNbO 3 crystal owns significant electrooptical properties, and nonlinear optical properties over wideband optical transparency. [26][27][28][29][30] Kinds of optical devices have been realized in integrated systems based on LN, such as electro-optic Q-switch, high-speed modulator, broadband wavelength converter, etc. [31][32][33][34] In this work, we have fabricated the Type-I and Type-II modifications with different processing parameters inside the y-cut LiNbO 3 crystal.…”