Fig. 1: Roadmap of the 30-year development of optical vortices from 1989 to 2019, including significant theoretical and technical breakthroughs with corresponding references.
From: Optical vortices 30 years on: OAM manipulation from topological charge to multiple singularities
Reprinted with permission from ref. 1, Copyright (2019), with permission from Elsevier. Reprinted with permission from refs. 5,16,19,25,27,28,38,40. Copyright (2019) by the American Physical Society. From refs. 29,32,33,41,42,44,46,47. Reprinted with permission from AAAS. Reprinted by permission from Springer Nature: Nature30,34,59,60, Nature Physics31,39, Nature Photonics43,50,52, Nature Communications48,49, Light: Science & Applications51, Copyright (2019). From ref. 57. Reproduced by permission of IOP Publishing
