512-Fold Rotational Super-Resolution via Four-Photon High-Dimensional Structured Light

Structured light enhances quantum information processing by combining quantum states of light and shaped wavefronts. However, until now, the advantages of high photon-number states and of structured light have only been demonstrated separately. Here, we report a rotation sensor that combines (Formula presented.) -dimensional spatial modulation with four-photon quantum states, yielding significantly improved angular resolution that scales as their product, (Formula presented.). Our work shows that it is possible to use both multi-photon states of light together with high spatial mode numbers, opening avenues in quantum sensing, communications, and quantum computing.