Silicon mode (de)multiplexers with parameters optimized using shortcuts to adiabaticity

We propose and experimentally demonstrate broadband silicon mode (de)multiplexers based on the optimization of system adiabaticity using shortcuts to adiabaticity (STA). The measured insertion losses and crosstalks were less than 1.1 dB and -24 dB, respectively, for the five two-mode mode-division-multiplexing (MDM) links over wavelengths ranging from 1500 nm to 1600 nm. The four-mode MDM link showed measured insertion losses and crosstalks less than 1.3 dB and -23 dB, respectively, within the same wavelength range. The method paves the way for future adaptation of the STA protocols to various components.