50 Gbit/s PAM4 Data Transmission Over 500-m Single-Mode Fiber Using an 880-nm Single Mode VCSEL

Error-free 50 Gbit/s PAM4 data transmission over 500-m single mode fiber was successfully realized using our oxide-confined 880-nm single-mode high-speed VCSELs. This transmission was accomplished because of the flat frequency response of the VCSEL across a wide bias span. Static characteristics and high-speed modulation properties at room temperature and high operation temperature were studied in detail. Data transmission experiments for the 880-nm VCSEL with 4- $\mu \text{m}$ oxide-aperture diameter was performed. A 50-Gbps PAM4 module was packaged for data transmission. Error-free 50 Gbit/s PAM4 data transmission over 500-m single mode fiber was successfully realized. The proposed VCSEL is fit for the 400G DR8 module because of its 500-m single-channel 50 Gbit/s error-free transmission. Compared with commonly used DML, VCSELs are evidently advantageous in cost and power consumption.