Enhanced Dichroic Coloration Through Void‐Particle Induced Interference in Randomly Distributed Cu ₂ O Octahedrons on Glass Substrate

Abstract While structural color generation from unique photonic and plasmonic nanoparticle arrays has been extensively studied, most particle‐based color generation mechanisms primarily rely on particle resonance, overlooking the structural contribution and substrate effects, particularly in disordered particle clusters. This work reports two new findings. First, material absorption of the particles can emphasize a single resonant mode while suppressing multiple Mie‐type resonances, simplifying the color rendering and design process. Second, the absence of particles in certain areas of a random array can contribute to a unique “void‐particle induced interference” influencing the overall color exhibited by these structures. Two distinct color modes observed in reflection, combined with a single mode transmission, give rise to a unique dichroism. By controlling the nanoparticle size and the effective area of voids and particles, it is possible to regulate the color realizations of such structures. The iridescent reflected color and fixed transmitted color at different viewing angles are also unique in this structure, and further validate the proposed color generation mechanism. This finding may provide a new approach for other materials to achieve exceptional optical phenomena.