Zhou Hongyin, Liao Kun, Su Zhaoxian, Li Tianhao, Geng Guangzhou, Li Junjie, Wang Yongtian, Hu Xiaoyong, Huang Lingling
Beijing Engineering Research Center of Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China.
State Key Laboratory for Mesoscopic Physics & Department of Physics, Collaborative Innovation Center of Quantum Matter, Beijing Academy of Quantum Information Sciences, Nano-optoelectronics Frontier Center of Ministry of Education, Peking University, Beijing 100871, China.
Nanophotonics. 2023 Feb 17;12(6):1105-1114. doi: 10.1515/nanoph-2022-0638. eCollection 2023 Mar.
Tunable mode converter is a key component of channel switching and routing for optical communication system by adopting mode-division multiplexing. Traditional mode converter hardly implements high-order mode conversion and dynamic tunability simultaneously. In this study, we design a tunable mode converter filled with liquid crystal, which can convert fundamental mode into multiple high-order modes (TE, TE, and TE) with a good performance and low intrinsic loss. For this multiple-objective task, we propose an inverse design framework based on the adjoint method. To experimentally prove our design, a tunable mode converter filled with air or water and a mode demultiplexer are fabricated to implement dynamic routing. The experimental results agree well with the simulation and reveal the crosstalk only around -7 dB. With its performance and efficiency, our proposed design flow can be a powerful tool for multifunction device design.
可调谐模式转换器是采用模式分割复用的光通信系统中通道切换和路由的关键组件。传统模式转换器很难同时实现高阶模式转换和动态可调性。在本研究中，我们设计了一种填充液晶的可调谐模式转换器，它可以将基模高效地转换为多个高阶模式（TE、TE和TE），且固有损耗低。针对这一多目标任务，我们提出了一种基于伴随方法的逆向设计框架。为了通过实验验证我们的设计，制作了一个填充空气或水的可调谐模式转换器和一个模式解复用器来实现动态路由。实验结果与模拟结果吻合良好，串扰仅约为-7 dB。凭借其性能和效率，我们提出的设计流程可以成为多功能器件设计的有力工具。
