Abstract
A broadband thermo-optic Mach–Zehnder switch that can control two spatial modes simultaneously on a silicon chip is demonstrated in this Letter. A broadband multimode 3 dB coupler is first realized based on symmetrically coupled waveguides with a sub-wavelength structure. The length of the coupler is only 24.2 μm. By employing such a multimode 3 dB coupler together with symmetrical delay arms, an optical switching functionality is realized experimentally with excess losses less than 1.3 dB and crosstalks less than over a 60 nm bandwidth for the two spatial modes. An arbitrary splitting ratio at two output ports for the two modes simultaneously is also demonstrated when applying different currents on the heater.
© 2019 Optical Society of America
Full Article | PDF ArticleMore Like This
Kaixuan Chen, Siya Wang, Sitao Chen, Shipeng Wang, Chenzhao Zhang, Daoxin Dai, and Liu Liu
Opt. Lett. 40(20) 4655-4658 (2015)
Hongnan Xu and Yaocheng Shi
Opt. Lett. 41(20) 4815-4818 (2016)
Kai Chen, Fei Duan, and Yonglin Yu
Opt. Lett. 44(4) 951-954 (2019)