Full-space inverse-designed meta-optics for complex vector field shaping of intracavity landscapes

The sophisticated shaping of electromagnetic field landscapes, both outside and inside optical cavities, has long been an important goal of optics and photonics, with broad applications in near-field imaging, lithography, and laser science. Despite extensive progress in far-field shaping of extracavity landscapes, achieving accurate tailoring of three-dimensional intracavity fields has remained elusive. Here, we propose full-space adjoint-enabled freeform meta-optics for complex, on-demand vector field shaping of intracavity landscapes. In contrast with conventional semi-space adjoint approaches, the full-space adjoint strategy allows for efficient full-wave optimization of vector fields at the subwavelength scale, overcoming strong multiple scattering and interference intrinsic to enclosed cavity boundaries. We experimentally demonstrate tailored plasmonic cavity landscapes with a freeform metasurface mask, realizing a fivefold enhancement in imaging fidelity without sacrificing optical super-resolution performance. Our work significantly broadens the scope of freeform meta-optics and may open new avenues for applications in nanophotonics, topological photonics, and quantum optics.