Plasmon antenna array “patchwork” lasers – towards low etendue, speckle free light sources

In this work, we study plasmon antenna array lasers for solid-state lighting (SSL). Optically pumped plasmon antenna array lasers can provide benefits suitable for SSL including efficient pump-light absorption, high brightness, and good directivity. However, applying lasers in SSL is difficult because of speckle formation. To overcome this issue, we propose two types of lasers based on patchworks of small plasmon lattices with different lattice constants, tessellating an extended surface. The premise is that they could ultimately form a blue-LED pumped broad-area directional emitter with reduced coherence to suppress speckle. An important question is whether different patches couple when assembled together, and how this affects spatial and spectral profiles. In this paper, we show measurement results on the plasmon patchwork lasers, and discuss their modelling and potential application as low etendue and speckle free sources in SSL.