1.Xi 'an Key Laboratory of Microwave Photon and Optical Communication， Xi’an， 710121， China;2.School of Electronic Engineering， Xi’an University of Posts and Telecommunications， Xi’an， 710121， China
Supported by the National Natural Science Foundation of China （61875165）； the Key Research and Development Projects of Shaanxi Province （2022GY-008）； the International Cooperation and Exchange Projects of Shaanxi Province （2020KWZ-017）； the Collaborative Innovation Projects of Education Office of Shaanxi Province （20JY060）
A compact polarization splitter rotator （PSR） based on the principle of mode evolution is proposed. The device consists of a tapered TM0-TE1 mode converter and a mode splitter with an asymmetric directional coupler （ADC） structure， optimized by particle swarm optimization （PSO） and the principle of spline interpolation. The device is simulated using the finite difference time domain method （FDTD）. The numerical results show： for TE0 mode input， a low insertion loss （<0.007 dB）， low crosstalk （<-28.7 dB）， and high polarization extinction ratio （>49.1 dB） in the 100 nm （1500~1600 nm） bandwidth is achieved within a device length of only 45μm. On the other hand， for TM0 mode input， a low insertion loss （<0.34 dB）， low crosstalk （<-47.1 dB）， and high polarization extinction ratio （>15.5 dB） in the whole C-band is achieved. The insertion loss value at 1550 nm is reduced to 0.06 dB. In addition， the tolerance of the device is analyzed and the results reveal that the proposed device is robust. The designed PSR has small loss， compact size， and low crosstalk， which are important for future applications in large-scale photonic integration.
HUI Zhan-Qiang, LI Bin, LI Tian-Tian, HAN Dong-Dong, GONG Jia-Min. Silicon-based C-band low-loss compact polarization splitter rotator based on PSO algorithm[J]. Journal of Infrared and Millimeter Waves,2023,42(1):132~141Copy