Holographically fabricated, highly reflective nanoporous polymeric distributed Bragg reflectors with red, green, and blue colors [Invited]

We report holographic fabrication of nanoporous distributed Bragg reflector (DBR) films with periodic nanoscale porosity via a single-prism conuration. The nanoporous DBR films result from the phase separation in a material recipe, which consists of a polymerizable acrylate monomer and nonreactive volatile solvent. By changing the interfering angle of two laser beams, we achieve the nanoporous DBR films with highly reflective red, green, and blue colors. The reflection band of the nanoporous DBR films can be tuned by further filling different liquids into the pores inside the films, resulting in the color change accordingly. Experimental results show that such kinds of nanoporous DBR films could be potentially useful for many applications, such as color filters and refractive index sensors.