Two-dimensional photonic crystals from semiconductor material with polymer filled holes

Abstract

Polymer filling of the air holes of indiumphosphide based two-dimensional photonic crystals is reported. The filling is performed by infiltration with a liquid monomer and solidification of the infill in situ by thermal polymerization. Complete hole filling is obtained with infiltration under ambient pressure. This conclusion is based both on crosssectional scanning electron microscope inspection of the filled samples as well as on optical transmission measurements.

Assessing the performance of sustainable luminescent solar concentrators based on chemically recycled poly(methyl methacrylate)

“…The relatively high price of PMMA (∼3000-4000 € t −1 ) 18 compared to other highconsumption plastics such as polyolefins 19 makes its recycling worthwhile, although currently only 8 kt per year out of 300 are recycled in Europe. 20 Unlike mechanical recycling, in which polymeric materials are blended under heat, chemical recycling allows for depolymerization, yielding a regenerated monomer for new polymerization. Depolymerization of PMMA is achievable in high yield by an uncatalyzed pyrolysis process, 21 which can be performed on an industrial scale employing different technologies, such as dry distillation, the fluidized bed process, molten metal (or molten salt) baths, and extrusion.…”

InP-based planar photonic crystals infiltrated with solid polymers and liquid crystals

“…A possible route is the diffusion of the air through the liquid plug during the infiltration, driven by the quite high capillary pressure (up to ~ 5 bar if there would be no degassing). Although the gas permeability of the used liquid was not known, using typical data for polymers suggested that this route is indeed plausible, leading to degassing times (< 1 s), short compared to the time scale of the infiltration and subsequent polymerization process (> 10 3 s) 18 . To show whether infiltration under ambient works also for the Liquid Crystals (LC) that are usually infiltrated under vacuum, a sample was infiltrated with the common nematic Liquid Crystal known as 5 CB or K-15 (4-n-pentyl-4-cyanobiphenyl).…”