Fabrication of lithium niobate fork grating by laser-writing-induced selective chemical etching
Wang Tianxin,
Xu Xiaoyi,
Yang Lei,
Yan Shuo,
Hu Xueli,
Hu Xiaopeng,
Lu Xiaomei,
Xiao Min,
Zhang Yong
Affiliations
Wang Tianxin
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Xu Xiaoyi
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Yang Lei
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Yan Shuo
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Hu Xueli
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Hu Xiaopeng
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Lu Xiaomei
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Xiao Min
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
Zhang Yong
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
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 of LN crystal produces negative domains and domain walls. Also, it causes local lattice defects, in which the etching rates are significantly increased in comparison to the original LN crystal. In experiment, we use the LWISCE technique to fabricate various fork gratings in an X-cut LN crystal for the generation of vortex beams. In comparison to etching an untreated X-cut LN crystal, the etching rates of the laser-writing-induced boundaries and the central laser-irradiated areas are enhanced by a factor of 26 and 16, respectively. The width and depth of fork grating structure can be precisely controlled by laser writing parameters. Our method provides an efficient mask-free micro-fabrication technique for LN crystal, which can be readily applied to other ferroelectric crystals such as lithium tantalate, potassium titanyl phosphate and barium calcium titanate.
