Prof. Shlomi Arnon

Light beams carrying Orbital Angular Momentum (OAM) are of broad interest in fundamental optics and have important applications in communication, sensing, and metrology. Conventional techniques require capturing full-beam spot with large optics, restricting scalability and integration. In this work, we demonstrate that both the order and sign of OAM modes can be identified by sampling only a small part of the beam. Reliable mode discrimination was achieved using only of the beam cross-section. Experiments with agreed with analytical predictions within error, and simulations up to confirmed systematic order-dependent shifts. This localized sampling approach provides a hardware-efficient and scalable pathway for OAM detection in optical communication, metrology, and integrated photonics.