Spatial-to-Temporal Orbital Angular Momentum Mapping in Twisted Light Fields

Optical angular momentum (OAM) in light beams is manifested as the two-dimensional spatial distribution of its complex amplitude, necessitating a 2D detector for its measurement. Here we present a novel speckle-based machine learning approach for OAM recognition, which enables recognition using a 1-D array detector or even a 0-D single-pixel detector.