Japanese scientists have developed a new type of DFB laser, which can achieve high-speed 200Gbps transmission in a range of 10 kilometers.

Thanks to CTOnews.com netizen Brother Black fly's left hand clue delivery! CTOnews.com, January 16, Japanese scientists have recently developed a new type of distributed feedback (DFB) laser, which shows that it can transmit data at a speed of 200 Gb / s in a range of 10 kilometers. This research can promote the development of network technology and enable Internet data centers to process data faster.

Kazuki Nishimura, an optical engineer in the data communications business unit of Lumentum Japan, Japan, will present the new research at the Optical Fiber Communications Conference (OFC) in San Diego, California, USA, March 5-9, 2023.

"this research will contribute to the development of next-generation 800G and 1.6T Ethernet data centers," Nishimura said. In particular, this new technology shows that electroabsorption modulators integrated with distributed feedback (EA-DFB) lasers can achieve 10km transmission using traditional PAM4 (pulse amplitude modulation) technology, which is currently defined as a simple intensity modulation direct detection (IM / DD) scheme.

CTOnews.com learned that with the continuous increase of traffic, technologies such as 800G and 1.6T Ethernet are getting more and more attention. The current PAM4 technology for 2km 400G transmission can be considered for 800G networks, but new technologies need to be developed to expand data transmission capacity over longer distances between data center areas or campuses.

In the process of this development, the researchers developed a lumped electrode electroabsorption (EA) modulator DFB laser to achieve a longer distance. They first demonstrated the 5km transmission of 225-Gb / s PAM4 using a new laser at 50 °C using a coarse wavelength division multiplexing (CWDM) band. The researchers then used the laser to transmit 225-Gb / s PAM4 for 10 kilometers at 1293.5 nm.

In all experiments, the new laser shows lower closed quaternion (TDECQ) values of emitter and dispersion eye pattern, indicating that the performance of the transmitter is reliable. The researchers say their results demonstrate the potential of lumped EA-DFB lasers as a light source for 800G Ethernet technology and can achieve high-speed data transmission at 10km. The study can also be applied to CWDM4 applications with longer distances.