Enhanced Spontaneous Light Emission of ZnO Nanowire-Based Gratings

We theoretically and experimentally investigated the spontaneous light emission of ZnO nanowires (NWs) arranged in grating structures. Through systematic calculations of light extraction and absorption efficiencies together with the Purcell factor, we shed light on the influence of disorder on these optical processes. This analysis unveils the role of optical resonances to achieve direct light extraction and to enhance the spontaneous emission. We demonstrate that the periodic structuring of the ZnO NWs at the micrometer scale is a robust and efficient solution to increase the spontaneous emission efficiency.