Original ResearchPublished 11 September 2026Four-beam OAM-based unipotent single-entry code for high-capacity 40 × 16 Gbps FSO linksSyed Mohammad Ammar · Hassan Yousif Ahmed · Syed Alwee Aljunid · Medien Zeghid · Sami Mourou · Norshamsuri AliFrontiers in Physicsdoi 10.3389/fphy.2026.1909399