Plasmonic device, method of manufacturing a plasmonic device and method of analysis using a plasmonic device

A plasmonic device comprising:

• a base substrate formed from a polymer material, and
• an electrically conductive film formed on the base substrate;
• wherein the base substrate has;
• a reference upper surface;
• and
• an arrangement of chiral nanostructures formed in relief from the reference upper surface;
• each chiral nanostructure having a nanostructure upper surface which is disposed at a distance of at least 30 nm from the reference upper surface in a thickness direction, wherein the chiral nanostructures formed in relief are formed as one of;
• (i) indentations in the reference upper surface, with the nanostructure upper surface recessed from the reference upper surface;
• and
• (ii) protrusions from the reference upper surface, with the nanostructure upper surface protruding from the reference upper surface;
• and
• wherein the electrically conductive film is formed continuously on the nanostructure upper surface of each chiral nanostructure and on at least part of the reference upper surface of the base substrate with part of the electrically conductive film forming an electrical connection between the electrically conductive film on the nanostructure upper surface and the electrically conductive film on the said at least part of the reference upper surface.