Figure 2.

SEM images and SAXS data for a selection of meso-structures. (a) A pattern of concentric rings generates a strong isotropic ring of scattering; this structure is used as an amplifier. (b) A 5 × 5 hexagonal arrangement of 23 dots, fabricated as a test sample. (c) A 3 × 3 hexagonal arrangement of 8 dots, which acts as a very weakly scattering sample. (d) When there is coherent interference between a sample and the amplifier (in this example, by patterning them side by side on a single substrate), fringes appear in the scattering pattern, wherever both sample and amplifier scatter strongly. (e) In the case of a very weakly scattering sample (which cannot be discerned above the experimental background), coherent interference with the amplifier nevertheless generates a visible fringe pattern. In other words, although the sample alone cannot be resolved, coherent amplification can be used to infer the sample’s scattering pattern.