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 LP₂₁-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 3D 拓扑能力、大透明窗口和低耦合色散而成为构建混合 3D 光子电路的有前途的波导平台。目前，将台式光学系统缩小到玻璃芯片的关键挑战是缺乏控制 3D 波导电路的模场和光耦合的精确方法。在这里，我们提出了一种基于激光直接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。在此方法的基础上，我们实现了可变模场分布、稳健的宽带耦合，从而演示了超连续谱脉冲的无色散LP ₂₁模式转换，在210 nm宽带上耦合比的最大偏差<0.1 dB。这种方法提供了在 3D 光子电路中实现超宽带和低色散耦合的途径，与传统的平面波导光学平台相比，在超短激光脉冲和宽带超连续谱的片上传输和操纵方面具有压倒性的优势。