Research on Multi-core Optical Fiber, the Foundation of the New Era of High-capacity Communications, and Amplification to Limit Power Increases

The optical fibers that underpin current communications are single-mode optical fibers (SMFs), which have only one core (the path through which light travels).The transmission capacity limit of SMFs is reportedly 100 Tbit/s.Meanwhile, communication volume is expected to continue to increase, and current SMFbased communications may reach its limit between 2030 and 2040.In response to this, development of multi-core optical fibers (MCFs) is underway.We spoke with NTT Distinguished Researcher Taiji Sakamoto, who is researching and developing MCFs with up to 12 cores in a single optical fiber as well as optical amplifiers that limit the increased power consumption that results from an increase in the number of cores.