Photothermal modification of high index dielectric structures

There is presented a method for geometrically modifying high-index dielectric structures on a support structure, said method comprising providing a support structure, a first plurality of high-index dielectric structures being supported by the support structure, said method further comprising changing a geometry specifically of high-index dielectric structures within a second plurality of high- index dielectric structures, wherein the second plurality of high-index dielectric structures is a sub-set of the first plurality of high-index dielectric structures, wherein said changing the geometry is carried out by photothermally melting at least a portion of each of the high-index dielectric structures within the second plurality of high-index dielectric structures by irradiating the second plurality of high-index dielectric structures with incident electromagnetic radiation having an incident intensity in a plane of the second plurality of high-index dielectric structures, and thereby exciting resonances associated with each of the high- index dielectric structures within the second plurality of high-index dielectric structures, wherein said support structure comprises a first plurality of topographical features, and wherein the first plurality of high-index dielectric structures are given by high-index dielectric structures on or in said topographical features, and/or holes in a high-index dielectric film, wherein said holes correspond to said topographical features.