Wang Yuying, Zhong Lijing, Lau Kuen Yao, Han Xuhu, Yang Yi, Hu Jiacheng, Firstov Sergei, Chen Zhi, Ma Zhijun, Tong Limin, Chiang Kin Seng, Tan Dezhi, Qiu Jianrong
College of Optical Science and Engineering, Zhejiang University, 310027, Hangzhou, China.
Institute of Light+X Science and Technology, College of Information Science and Engineering, Ningbo University, 315211, Ningbo, China.
Light Sci Appl. 2024 Jun 4;13(1):130. doi: 10.1038/s41377-024-01473-7.
Three-dimensional (3D) glass chips are promising waveguide platforms for building hybrid 3D photonic circuits due to their 3D topological capabilities, large transparent windows, and low coupling dispersion. At present, the key challenge in scaling down a benchtop optical system to a glass chip is the lack of precise methods for controlling the mode field and optical coupling of 3D waveguide circuits. Here, we propose an overlap-controlled multi-scan (OCMS) method based on laser-direct lithography that allows customizing the refractive index profile of 3D waveguides with high spatial precision in a variety of glasses. On the basis of this method, we achieve variable mode-field distribution, robust and broadband coupling, and thereby demonstrate dispersionless LP-mode conversion of supercontinuum pulses with the largest deviation of <0.1 dB in coupling ratios on 210 nm broadband. This approach provides a route to achieve ultra-broadband and low-dispersion coupling in 3D photonic circuits, with overwhelming advantages over conventional planar waveguide-optic platforms for on-chip transmission and manipulation of ultrashort laser pulses and broadband supercontinuum.
三维（3D）玻璃芯片因其三维拓扑能力、大透明窗口和低耦合色散，是构建混合3D光子电路的有前景的波导平台。目前，将台式光学系统缩小到玻璃芯片的关键挑战在于缺乏精确控制3D波导电路模式场和光耦合的方法。在此，我们提出一种基于激光直写光刻的重叠控制多扫描（OCMS）方法，该方法允许在各种玻璃中以高空间精度定制3D波导的折射率分布。基于此方法，我们实现了可变模式场分布、稳健且宽带的耦合，从而证明了超连续脉冲的无色散LP模式转换，在210nm宽带的耦合比中最大偏差<0.1dB。这种方法为在3D光子电路中实现超宽带和低色散耦合提供了一条途径，与用于片上传输和操纵超短激光脉冲及宽带超连续谱的传统平面波导光学平台相比具有压倒性优势。
