Study And Design Of High Speed Multichannel Mach-zehnder Modulator

With the development of integrated circuit technology,EPIC(Electronic-photonic Integrated Circuit)based on CMOS technology has already made great process.It has become possible that integrates multiple optical and electrical devices in a same chip.EPIC technology combines the advantages of high-bandwidth,low-loss optical interconnects with the largescale integration of CMOS integrated circuits that makes it easy to implement high-speed,high-bandwidth,multi-channel and low power electro-optical interconnect interface.EPIC has become an effective solution of high speed multi-channel optical interfaces in access networks,high performance computing and data centers.The multi-channel highspeed electro-optic modulator based on EPIC technology is an important part of the interface to realize high bandwidth electrooptical interconnection,which is worthy of further study.In this paper,we demonstrated a design of compact multi-channel MachZehnder Modulator(MZM),aiming at the application requirements of the network interconnection interface of the next generation supercomputer system.We analysis the principle of the MZM and set up the traveling wave electrode model,distributed circuit model and distributed electro-optical modulation model.A high-speed and compact traveling-wave MachZehnder modulator is designed based on these models,and the crosstalk problem between the channels is optimized based on the method of connecting ground electrodes.Based on the IMEC silicon photonics SOI process,we have implemented a high-speed,multi-channel Mach-Zehnder modulator chip with a total area of 3mm×1.2mm(four channels).The simulation results show that the circuit can achieve single-channel electro-optic modulation bandwidth of 21.3GHz with the parallel data rate up to 4×25Gbps.Through connecting the ground electrodes,crosstalk between channels is reduced to less than-40 d B within the frequency range of 30 GHz.And the bit error rate(BER)has been significantly reduced.