Fabrication of lithium niobate fork grating by laser-writing-induced selective chemical etching

Abstract We propose and experimentally demonstrate a laser-writing-induced selective chemical etching (LWISCE) technique for effective micro-fabrication of lithium niobate (LN) crystal. Laser writing LN crystal produces negative domains domain walls. Also, it causes local lattice defects, in which the rates are significantly increased comparison to original In experiment, we use LWISCE fabricate various fork gratings an X-cut generation vortex beams. untreated crystal, boundaries central laser-irradiated areas enhanced by factor 26 16, respectively. The width depth grating structure can be precisely controlled laser parameters. Our method provides efficient mask-free readily applied other ferroelectric crystals such as tantalate, potassium titanyl phosphate barium calcium titanate.