Optical 90° Hybrid Based on an InP 4×4 Multimode Interference Coupler for Coherent Receiver Application
LIU Wei-Hua1**, ZHAO Yan-Li1, XU Cheng-Zhi1, ZHAO Jian-Yi1, LIU Wen1, XU Yuan-Zhong2
1Wuhan National Laboratory for Optoelectronics, College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 2Wuhan Telecommunication Device Co. Ltd., Wuhan 430074
Optical 90° Hybrid Based on an InP 4×4 Multimode Interference Coupler for Coherent Receiver Application
LIU Wei-Hua1**, ZHAO Yan-Li1, XU Cheng-Zhi1, ZHAO Jian-Yi1, LIU Wen1, XU Yuan-Zhong2
1Wuhan National Laboratory for Optoelectronics, College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 2Wuhan Telecommunication Device Co. Ltd., Wuhan 430074
Abstract：An optical 90° hybrid based on an InP 4×4 multimode interference (MMI) coupler is designed and fabricated for the application in a coherent receiver. It reveals that the width of multimode waveguide is the most critical parameter for the devices, and the multimode waveguide width can be accurately controlled within 0.1 μm in our experiments. Across the entire C-band (1527–1561 nm), the maximum imbalance of the devices is less than 0.7 dB, and the common mode rejection ratios for in-phase channels and quadrature channels are better than -24 dB.
2012, Vol. 29 
