2023/07/03 by S. W. Hancock, S. Zahedpour, Hancock, S. W. +5 · 3 citations
Agricultural and Biological Sciences · Engineering · Physics and Astronomy · #FOS: Physical sciences #Optical Wireless Communication Technologies #Optics (physics.optics) #Orbital Angular Momentum in Optics #Plant and animal studies
paper · pdf · doi:10.48550/arxiv.2307.01019
openalex publication_date 2023/07/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We demonstrate the controlled spatiotemporal transfer of transverse orbital angular momentum (OAM) to electromagnetic waves: the spatiotemporal torquing of light. This is a radically different situation than OAM transfer to longitudinal, spatially-defined OAM light by stationary or slowly varying refractive index structures such as phase plates or air turbulence. We show that transverse OAM can be imparted to a short light pulse only for (1) sufficiently fast transient phase perturbations overlapped with the pulse in spacetime, or (2) energy removal from a pulse that already has transverse OAM. Our OAM theory for spatiotemporal optical vortex (STOV) pulses [Phys. Rev. Lett. 127, 193901 (2021)] correctly quantifies the light-matter interaction of this experiment, and provides a torque-based explanation for the first measurement of STOVs [Phys. Rev. X 6, 031037 (2016)].