2023 Volume 26 Issue 6 Pages 590-597
To increase the speed of the optical subassemblies used in data centers, we have developed an EML with a high-mesa structure and a high-speed electrical interface technology that suppresses reflections of electrical signals. In addition, the reflection at the connection between the PCB and the FPC, which is the electrical interface part, was successfully suppressed to less than 12 dB over a bandwidth of 50 GHz. A 43Gb/s EML optical subassembly with these technologies was fabricated and evaluated, resulting in excellent optical waveforms with a mask margin of over 11%. Furthermore, a fabricated 424 Gb/s EML optical subassembly with four EMLs integrated into a single package showed good optical waveform quality with TECQ less than 2.5 dB for all lanes.
