Figure 2. Design fabrication and experimental demonstration of bimetallic colour router.

(a) An artist's view of colour routing from a bimetallic dimer supported by a glass substrate. (b) Low- and high (inset)-magnification scanning electron microscopy images of bimetallic dimers produced by hole–mask colloidal lithography. Scale bar is 1 μm (inset: 200 nm). (c) Scheme of the experimental setup. White light from a halogen lamp passes through a polarizer and is loosely focused on the sample at normal incidence. The directly transmitted light is effectively filtered out by an opaque stop in the Fourier plane, while light scattered by the dimers at angles higher than the stop (NA∼0.9) passes through to the detectors, a fibre-coupled spectrometer and a charge-coupled device camera.