Nonlocal Leaky Mode Metasurfaces for Mode‐, Angle‐, and Polarization‐Multiplexed Holography With Thermal Light

ABSTRACT Metasurface holography has historically relied on laser illumination to provide the spatial and temporal coherence required for interferometric wavefront reconstruction. Here, we demonstrate multiplexed holography using spectrally filtered thermal halogen light via a nonlocal leaky mode metasurface. Unlike standard metasurfaces based on localized resonances (Quality factor, ), our prism‐coupled Multilayer Metal‐Cladded Leaky Waveguide (MMCLW) supports nonlocal leaky guided modes with Q 200 and angular selectivity . These modes enforce momentum matching to selectively couple discrete wavelength‐angle combinations from a broadband halogen source into spectrally purified output channels (). This spectral compression enhances temporal coherence by two orders of magnitude, placing the output chromaticities on the spectral locus of International Commission on Illumination 1931 chromaticity diagram, exceeding the standard red‐green‐blue colour gamut. We demonstrate three multiplexing schemes: mode‐wavelength multiplexing, mode‐angle multiplexing, and mode‐polarization multiplexing with distinct images reconstructed in each channel. This work establishes the nonlocal leaky mode metasurfaces as a platform for coherence‐demanding wavefront control using incoherent thermal sources, without lasers, external spectral filters, or active modulation.