Yuan Hongyi, Zhang Nianen, Zhang Hongyu, Lu Cuicui
Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education, Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China.
Nanomaterials (Basel). 2023 Jul 23;13(14):2133. doi: 10.3390/nano13142133.
Integrated frequency routers, which can guide light with different frequencies to different output ports, are an important kind of nanophotonic device. However, frequency routers with both a compact size and multiple channels are difficult to realize, which limits the application of these frequency routers in nanophotonics. Here, a kind of bandgap optimization algorithm, which consists of the finite element method and topology optimization, is proposed to design a multi-channel frequency router. Channels supporting photonic edge states with different frequencies are built through the synthetic dimension of translational deformation. Due to the help of the developed optimization algorithms, the number of channels and output ports can be increased up to nine while maintaining ultracompact device size. The device operates within a working band of 0.585-0.665 c/, corresponding to 1.504-1.709 μm when the lattice constant is set as 1 μm, covering the telecom wavelength of 1.55 μm. The average crosstalk is about -11.49 dB. The average extinction ratio is around 16.18 dB. Because the bus of the device can be regarded as a part of a topological rainbow, the results show that the structure is robust to fabrication errors. This method is general, which can be used for different materials and different frequency ranges. The all-dielectric planar configuration of our router is compact, robust, and easy to integrate, providing a new method for on-chip multi-channel broadband information processing.
集成频率路由器能够将不同频率的光引导至不同的输出端口，是一种重要的纳米光子器件。然而，同时具备紧凑尺寸和多通道的频率路由器难以实现，这限制了这些频率路由器在纳米光子学中的应用。在此，提出了一种由有限元法和拓扑优化组成的带隙优化算法来设计多通道频率路由器。通过平移变形的合成维度构建支持不同频率光子边缘态的通道。借助所开发的优化算法，在保持超紧凑器件尺寸的同时，通道数和输出端口数可增加至九个。该器件在0.585 - 0.665 c/的工作频段内运行，当晶格常数设为1μm时，对应波长为1.504 - 1.709μm，覆盖了1.55μm的电信波长。平均串扰约为 -11.49 dB。平均消光比约为16.18 dB。由于该器件的总线可被视为拓扑彩虹的一部分，结果表明该结构对制造误差具有鲁棒性。此方法具有通用性，可用于不同材料和不同频率范围。我们的路由器全介质平面配置紧凑、鲁棒且易于集成，为片上多通道宽带信息处理提供了一种新方法。
