基于光学相变材料Ge₂Sb₂Se₄Te₁和光波导结构,提出一种可重构的2×4模式复用光开关器件,用来提高光通信容量。该器件由两个含倾斜波导结构的1×2复用开关单元和一个结构对称的2×2复用开关单元构成。首先通过模式耦合理论分析波导中的模式传输特性,然后采用三维时域有限差分法对光开关器件进行建模,最后使用模型进行实验研究。研究结果表明,当工作波长为1550 nm时,1×2开关单元在相变材料为晶态和非晶态下的插入损耗分别低至0.60 dB和0.06 dB,消光比分别高达19.55 dB和27.58 dB;2×4模式复用开关在整个C波段(1530~1565 nm)插入损耗的最小值为0.23 dB,消光比的最大值为19.12 dB。

Based on the optical phase change material Ge₂Sb₂Se₄Te₁ and the optical waveguide structure, a reconfigurable 2×4 mode multiplexing optical switch device is proposed to improve the optical communication capacity. The device is composed of two 1×2 multiplexing switch units with a slanted waveguide structure and a 2×2 multiplexing switch unit with symmetrical structure. First, the mode transmission characteristics in the waveguide are analyzed by the mode coupling theory. Second, the optical switching device is modeled by the three-dimensional finite difference time domain method. Finally, the model is used for experimental research. The research results show that when the working wavelength is 1550 nm, the insertion loss of the 1×2 switch unit when the phase change material is in the crystalline state and the amorphous state is as low as 0.60 dB and 0.06 dB, and the extinction ratio is as high as 19.55 dB and 27.58 dB, respectively. The minimum insertion loss of the 2×4 mode multiplex switch in the entire C-band (1530--1565 nm) is 0.23 dB, and the maximum extinction ratio is 19.12 dB.