title: Focus issue introduction: space-division multiplexing.
abstract: Since the publication of the first focus issue [Opt. Express 19(11), 2011], single-fiber transmission capacity has eclipsed the 1 Pb/s mark. All aspects related to space-division multiplexing including fiber, passive components [(de)multiplexer, couplers], active components (EDFA and Raman amplifiers), switching and routing elements (ROADM and WSS), as well as transmission and networking have progressed rapidly. This focus issue is intended to bring together the most up-to-date research in space-division multiplexing, including fibers, passive and active components, transmission systems and networking.
authors.forename: Guifang
authors.initials: G
authors.lastname: Li
authors.forename: Magnus
authors.initials: M
authors.lastname: Karlsson
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.forename: Yves
authors.initials: Y
authors.lastname: Quiquempois
mesh_terms: D003195:Computer Communication Networks; D055096:Optical Devices; D012815:Signal Processing, Computer-Assisted; D013685:Telecommunications