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

ABSTRACT 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 ‐dimensional spatial modulation with four‐photon quantum states, yielding significantly improved angular resolution that scales as their product, . 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.