Fig. 3From: Underwater transmission of high-dimensional twisted photons over 55 metersExperimental results of higher-order superposition states. a. Simulation and measured modal structures of second- and third-order superposition states. The double-headed arrow illustrates the identified orientation of modal structure with our angle recognition algorithm. b. Real-time fidelity measurement of third-order superposition states. The fluctuation of fidelities over 27 seconds is found less than 1.1%Back to article page