Sun Lu, Li Xingfeng, Hu Pan, Wang Hongwei, Zhang Yong, Tang Guojing, He Xintao, Dong Jianwen, Su Yikai
State Key Lab of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China.
Nanophotonics. 2024 Oct 28;13(24):4459-4470. doi: 10.1515/nanoph-2024-0437. eCollection 2024 Nov.
Valley photonic crystals (VPCs) provide an intriguing approach to suppress backscattering losses and enable robust transport of light against sharp bends, which could be utilized to realize low-loss and small-footprint devices for on-chip optical communications. However, there are few studies on how to achieve power-efficient tunable devices based on VPCs, which are essential for implementing basic functions such as optical switching and routing. Here, we propose and experimentally demonstrate a thermally tunable add-drop filter (ADF) based on VPCs operating at telecommunication wavelengths. By leveraging the topological protection of the edge state and the distinct property of negligible scattering at sharp bends, a small footprint of 17.4 × 28.2 μm and a low insertion loss of 2.7 dB can be achieved for the proposed device. A diamond-shaped microloop resonator is designed to confine the light and enhance its interaction with the thermal field generated by the microheater, leading to a relatively low power of 23.97 mW needed for switching the output signal from one port to the other. Based on the thermally tunable ADF under the protection of band topology, robust data transmission is implemented with an ultrahigh data rate of 132 Gb/s. Our work shows great potential for developing high-performance topological photonic devices with the thermally tunable silicon-based VPCs, which offers unprecedented opportunities for realizing topologically protected and reconfigurable high-speed datalinks on a chip.
谷光子晶体（VPCs）提供了一种引人入胜的方法来抑制背向散射损耗，并实现光在急剧弯曲处的稳健传输，这可用于实现用于片上光通信的低损耗和小尺寸器件。然而，关于如何基于VPCs实现功率高效的可调谐器件的研究很少，而这些器件对于实现诸如光开关和路由等基本功能至关重要。在此，我们提出并通过实验证明了一种基于工作在电信波长的VPCs的热可调谐分插复用滤波器（ADF）。通过利用边缘态的拓扑保护以及在急剧弯曲处散射可忽略不计的独特特性，所提出的器件可实现17.4×28.2μm的小尺寸和2.7dB的低插入损耗。设计了一个菱形微环谐振器来限制光并增强其与微加热器产生的热场的相互作用，从而将输出信号从一个端口切换到另一个端口所需的功率相对较低，仅为23.97mW。基于带拓扑保护的热可调谐ADF，以132Gb/s的超高数据速率实现了稳健的数据传输。我们的工作展示了利用热可调谐硅基VPCs开发高性能拓扑光子器件的巨大潜力，这为在芯片上实现拓扑保护和可重构的高速数据链路提供了前所未有的机会。
