Optics in South Asia: introduction.

This feature issue is motivated by a recent upswing in optical and photonic research in South Asia and its increasing influence on both the scientific community and regional economies. In response, JOSA A and JOSA B have launched this feature issue on Optics in South Asia, focusing on work from Bangladesh, India, Nepal, Pakistan, and Sri Lanka. To maintain the standards of JOSA A and JOSA B, all submissions underwent a rigorous peer-review process. The issue highlights ongoing outstanding research in optics and photonics in South Asia, covering topics that span the full scopes of both journals-from classical optics, image science, and vision (JOSA A) to fundamental studies of light-matter interaction, including quantum optics, nonlinear optics, and laser physics (JOSA B). In total, 94 manuscripts were submitted; following review, 19 papers were accepted in JOSA A and 51 in JOSA B, among which are eight invited review articles. This feature issue offers researchers in South Asia a platform to present their latest findings across the full breadth of optics, including emerging and rapidly evolving areas in the discipline.