Engineered hyperuniformity for directional light extraction

Abstract

By leveraging the concept of isotropic stealthy hyperuniform arrays (ISHAs), in this paper, we design and experimentally demonstrate novel scattering arrays of dielectric nanoparticles, here referred to as optimized isotropic scattering arrays (OISAs), which give rise to ring-shaped regions in Fourier space (k-space), with intensity optimized by the collective coordinate optimization method. These arrays feature the ideal circular k-space structure required to achieve enhanced directional light extraction from light emitting devices (LEDs), with significantly reduced diffuse scattering compared with both Poisson random point patterns and Vogel spiral arrays. Enhanced directional emission from OISAs is demonstrated experimentally on large-scale arrays (1 × 1 mm2) of TiO2 nanoparticles fabricated atop LED ceramic converter materials. The enhanced directional light emission of OISAs of dielectric nanoparticles demonstrated in this work make them very attractive candidates for integration with commercially available LED active materials.