We propose and experimentally demonstrate a novel design approach for scalable 3-port and 4-port mode insensitive multimode switching matrices for the first two quasi-transverse electric (TE) modes. The mode insensitive phase shifter ensures less power consumption for simultaneous multimode signal transmission in a mode division multiplexing (MDM) network. At 1550 nm, the 3-port switch exhibits approximately 2.6 dB and 3.3 dB insertion loss for the longest path with a crosstalk of at most 10 dB and 8 dB over a bandwidth of 40 nm (1530 nm to 1570 nm) for TE0{\mathrm {TE}}_{\mathrm {0}} and TE1{\mathrm {TE}}_{\mathrm {1}} modes, respectively. The insertion loss measured for the 4-port switch is approximately 2.7 dB and 3.6 dB at 1550 nm with a corresponding crosstalk less than 8 dB for the two TE modes, respectively. The payload transmission is also performed using both 10 Gb/s non-return-to-zero (NRZ) and 14.0625 Gbaud 4-level pulse-amplitude modulation (PAM4) pseudorandom binary sequence (PRBS)-31 data signal to analyze the performance of the switches. Clear open eyes are observed for both single-mode and simultaneous two-mode transmissions. The low insertion loss, low intermodal crosstalk over a large optical bandwidth, and the clear open eye validate the scalability of the proposed switches for larger port count and higher-order modes.

中文翻译：

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可扩展的两模式 3 端口和 4 端口模式不敏感硅光子开关


我们提出并通过实验证明了一种新颖的设计方法，用于前两种准横向电（TE）模式的可扩展 3 端口和 4 端口模式不敏感多模开关矩阵。模式不敏感移相器确保模分复用 (MDM) 网络中同时多模信号传输的功耗更低。在 1550 nm 处，3 端口交换机的最长路径的插入损耗约为 2.6 dB 和 3.3 dB，对于 TE0{\分别为 mathrm {TE}}_{\mathrm {0}} 和 TE1{\mathrm {TE}}_{\mathrm {1}} 模式。 4 端口交换机在 1550 nm 处测得的插入损耗约为 2.7 dB 和 3.6 dB，两种 TE 模式的相应串扰分别小于 8 dB。还使用 10 Gb/s 不归零 (NRZ) 和 14.0625 Gbaud 4 级脉冲幅度调制 (PAM4) 伪随机二进制序列 (PRBS)-31 数据信号执行有效负载传输，以分析开关。对于单模和同时双模传输都可以观察到清晰的睁开眼睛。低插入损耗、大光带宽上的低模间串扰以及清晰的睁眼图验证了所提出的开关对于更大端口数和高阶模式的可扩展性。