Revisiting the parking problem under the light of random plasmonic arrays and metasurfaces

For a long time, random and complex media have been solely considered as a nuisance for controlling waves. Development of techniques such as time reversal, wave shaping with SLM and SMM have allowed to harness the very high numbers of degrees of freedom that those media intrinsically support. Hence random media were shown to improve focusing compared to free space or to increase the bit rate in telecommunications, to create media with very large bandgaps or to increase the absorption. Lastly metasurfaces, 2D devices designed at the subwavelength scale have brought considerable attention in photonics. Their capabilities to control the phase and the amplitude of waves lead to the design of flat lenses, holograms... Metasurfaces are designed in a periodic framework. To break this paradigm and harness the disorder for metasurfaces, processes like the near field coupling between elements as well as the packing of random elements must be thoroughly investigated. Here, we present our study of rectangular plasmonic particles of the order of 150 to 500 nm long, dispersed on a 2D plane. We investigate the maximum density achievable as a function of their aspect-ratio, as well as the local order and their optical consequences.