Novel nanosphere lithography to fabricate tunable plasmonic metasurfaces
In conventional nanosphere lithography, the nanosphere configurations in the layers are determined by a spontaneous self-assembly process. Therefore, the final configurations are limited to those with or close to the minimal free energy giving rise to very simple patterns. Researchers have now managed to circumvent this thermodynamical restriction by putting the monolayers in a confined environment and constructing the bilayers with sequential stacking, both of which are critical for the formation of moire patterns.