The optical switches for single-mode operation cannot be directly utilized in optical communication and interconnect systems adopting mode-division multiplexing. In this paper, three general architectures for on-chip optical space and mode switching are proposed, which are optimized for optical space switching, optical space switching plus local optical mode switching, and global optical mode switching, respectively. A silicon thermo-optic $2\times 2$ four-mode optical switch is demonstrated. The minimum and maximum optical link insertion losses are 16.0 and 20.9 dB (including $\sim 6\mathrm{dB}$ coupling loss), respectively, in the wavelength range of 1525–1565 nm, while the optical signal-to-noise ratios of the optical links are larger than 15.3 dB. The optical power penalty at a bit error rate of ${10}^{-9}$ varies from 1.0 to 5.6 dB for 40 Gbps data transmission through different optical links. This work provides a systematic solution to on-chip information switching for different physical and mode channels.

中文翻译：

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片上光学空间和模式切换的通用架构

用于单模操作的光开关不能直接用于采用模分复用的光通信和互连系统中。本文提出了三种片上光空间和模式切换的通用架构，分别针对光空间切换，光空间切换加局域光模式切换和全局光模式切换进行了优化。硅热光$\mathrm{2个}\times \mathrm{2个}$演示了四模式光开关。最小和最大光链路插入损耗为16.0和20.9 dB（包括$〜6\mathrm{D\; b}$耦合损耗）分别在1525–1565 nm的波长范围内，而光链路的光信噪比则大于15.3 dB。误码率为的光功率损失为${10}^{-9}$通过不同的光链路进行40 Gbps数据传输时，范围从1.0 dB到5.6 dB不等。这项工作为针对不同物理和模式通道的片上信息交换提供了系统的解决方案。