Multicore and multimode optical amplifiers for space division multiplexing

Abstract Space division multiplexing (SDM) has attracted considerable attention within the fiber optics communication community as a very promising approach to significantly increase the transmission capacity of a single optical fiber and to reduce the overall cost per transmitted bit of information. Various SDM transmission fibers, for example, multicore fibers and multimode fibers, have been introduced, and a more than 100-fold capacity increase (~10 Pbit/s) relative to conventional single-mode fiber systems has successfully been demonstrated. Also, a wide range of new SDM components and SDM amplifiers has accordingly been developed, with most now realized in a fully fiberized format. These fully integrated devices and subsystems are one of the key requirements for the deployment of practical SDM in future networks due to their potential for cost-, energy-, and space-saving benefits. In this chapter, we review the state of the art in optical amplifiers for the various SDM approaches under investigation, with particular focus on multicore and multimode devices.