The polarization beam splitter is a key component for polarization manipulation in photonic integrated circuits, but it is challenging to design for low-refractive-index optical materials, due to the low birefringence of the waveguides. We propose what we believe is a novel compact vertical-dual-slot waveguide-based coupling scheme for silicon carbide, enabling efficient low-birefringence polarization splitting by extensively modulating the transverse-magnetic mode distribution. We numerically and experimentally demonstrate the device in the 4H-silicon-carbide-on-insulator integrated platform, with a small footprint of 2.2μm×15μm. The device, easy to fabricate via a single lithography process as other components on the chip, exhibits low insertion loss of <0.71dB and <0.51dB for the transverse-electric and transverse-magnetic polarized light, respectively, and polarization extinction ratio of >13dB, over 80 nm wavelength range.

针对卫星光网络中网络拓扑动态时变和业务类型多样化的问题，研究了在软件定义网络架构下保障服务质量的路由技术，提出了一种基于多业务的卫星光网络蚁群优化波长路由算法。通过改进蚁群算法的启发函数，将波长空闲率、时延、时延抖动、丢包率作为蚂蚁选路的重要依据，为业务选择了满足多种服务质量的最优路径；采用分组波长分配方法对不同等级的业务进行了区分服务，为不同业务分配了不同的波长集。仿真结果表明：与CL-ACRWA算法和Dijkstra算法相比，降低了卫星光网络的平均时延、平均时延抖动、平均丢包率，提高了波长利用率，同时也降低了高优先级业务的网络拥塞概率。

To achieve photon-pair generation scaling, we optimize the quality factor of microring resonators for efficient continuous-wave-pumped spontaneous four-wave mixing. Numerical studies indicate that a high intrinsic quality factor makes high pair rate and pair brightness possible, in which the maximums take place under overcoupling and critical-coupling conditions, respectively. We fabricate six all-pass-type microring resonator samples on a silicon-on-insulator chip involving gap width as the only degree of freedom. The signal count rate, pair brightness, and coincidence rate of all the samples are characterized, which are then compared with the modified simulations by taking the detector saturation and nonlinear loss into account. Being experimentally validated for the first time to the best of our knowledge, this work explicitly demonstrates that reducing the round-trip loss in a ring cavity and designing the corresponding optimized gap width are more effective to generate high-rate or high-brightness photon pairs than the conventional strategy of simply increasing the quality factor.