Author Affiliations
Abstract
1 School of Science, Shandong Jianzhu University, Jinan 250101, China
2 Shandong Key Laboratory of Optical Communication Science and Technology, School of Physical Science and Information Technology, Liaocheng University, Liaocheng 252059, China
3 Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
4 School of Physics, Shandong University, Jinan 250100, China
Lithium niobate (, LN) channel and ridge waveguides have been successfully fabricated by He ion implantation, which has energy of 500 keV and fluence of and is combined with lithography and the precise diamond dicing technique. The refractive index profile of the annealed LN planar waveguide was reconstructed. The propagation loss of the channel waveguide with a width of 10 µm and that of the ridge waveguides with widths of 25 µm and 15 µm were investigated by the end-face coupling method. In our work, the factors that affect the waveguide properties of channel and ridge waveguides were revealed.
lithium niobate waveguides ion implantation ridge waveguide channel waveguide Chinese Optics Letters
2022, 20(7): 071301
Author Affiliations
Abstract
School of Science, Shandong Jianzhu University, Jinan 250101, China
After the three-dimensional self-affine fractal random surface simulation, we use the optical scattering theory to calculate the deep Fresnel region speckle (DFRS) under consideration of the more strict shadowing effect. The evolution of DFRS with the scattering distance and the intensity probability distribution are studied. It is found that the morphology of the scatterer has an antisymmetric relationship with the intensity distribution of DFRS, and the effect of micro-lenses on the scattering surface causes the intensity probability distribution of DFRS to deviate from the Gaussian speckle in the high light intensity area.
speckle simulation shadowing effect deep Fresnel region Chinese Optics Letters
2021, 19(4): 041404
1 山东建筑大学理学院, 山东 济南 250101
2 山东师范大学物理与电子科学学院, 山东 济南 250014
将散斑场的研究拓展到超快激光领域, 进而引入了超快散斑的概念。首先在理论上研究了超快脉冲照明随机粗糙表面在菲涅耳衍射区域形成的超快散斑光场及其自相关函数，然后利用光场的自相关、强度系综平均和强度自相关等统计函数导出散斑强度自相关函数。发现超快散斑的强度相关随着时间的推迟逐渐呈现出周期性振荡的特征，且振荡频率依次增大。利用对菲涅耳衍射区超快散斑场的计算模拟，发现了诸如散斑颗粒随时间逐渐增大、颗粒中出现频率越来越大的干涉条纹以及干涉条纹由观察面两侧向中心方向依次消失等一系列全新的动态演化规律。
超快光学 散射 超快散斑 统计特性
