Soft plasmons with stretchable spectroscopic response based on thermally patterned gold nanoparticles.

Flexible photonic crystals are attractive devices owing to their multifold tunable parameters additionally introduced by soft substrates or by nanostructured, nano-doped, or nano-embedded soft matters. This not only extends significantly the intrinsic functions of photonic crystals, but also facilitates easy integration of the photonic crystal device into various optoelectronic and sensing systems. So far, flexible metallic photonic structures have been constructed on micrometer scales with complex fabrication procedures. Much simpler and more reproducible methods are expected to achieve such metamaterials in large scales and at low costs. In address to these challenges, we developed a straightforward approach to create soft plasmonic photonic crystals consisting of gold nanolines arranged on stretchable substrates with nanoscale periods, centimeter-scale areas, and high reproducibility using annealed gold nanoparticle colloids.