Managing the interference effects from multiple thin-layer structures allows for the control of optical transmittance and reflectance properties -often with very high precision. Widely used and technologically significant examples of such structures are antireflection coatings (ARCs) and distributed Bragg reflectors (DBRs), which rely on the careful control of destructive and constructive interference, respectively, between incident and reflected/transmitted radiation. While these structures have been known for over a century and have been extremely well investigated for many decades, the growing emergence of printable, large area electronics based on soluble materials brings a new emphasis. Namely the availability and use of materials in multilayer environments that are capable of transferring well-established ideas to a solution-based production.Here, we demonstrate the solution-fabrication of ARCs and all dielectric mirrors based on a DBR design utilizing alternating layers of recently developed organic/inorganic hybrid materials comprised of poly(vinyl alcohol) (PVAl), cross-linked with titanium oxide hydrates, and commercially available bulk commodity plastics. Our dip-coated ARCs exhibit an 88 % reduction in reflectance across the visible compared to uncoated glass, and fully solution-coated DBRs provide a reflection of >99 % across a 100 nm spectral band in the visible region. Detailed comparisons with transfer-matrix methods (TMM) highlight the excellent optical quality of the structures. The investigation also demonstrates the extremely low optical losses and impressive interface qualities the constituent layers exhibit. Furthermore, when exposed to elevated temperatures, the hybrid material can display a notable, reproducible and irreversible change in both the refractive index and film-thickness while maintaining excellent optical performance. In addition to allowing a degree of post-deposition tuning of the photonic structures, this may lend itself to thermo-responsive applications, including security features and product-storage environment monitoring.

The ability to modify or enhance the dielectric constant of semiconducting polymers can prove valuable for a range of optoelectronic and microelectronic applications. In the case of organic photovoltaics, increasing the dielectric constant of the active layer has often been suggested as a method to control charge generation, recombination dynamics, and ultimately, the power conversion efficiencies. In this contribution, the impact that the degree and pattern of fluorination has on the dielectric constant of poly(3‐octylthiophene) (P3OT), a more soluble analogue of the widely studied conjugated material poly(3‐hexylthiophene), is explored. P3OT and its backbone‐fluorinated analogue, F‐P3OT, are compared along with a block and alternating copolymer version of these materials. It is found that the dielectric constant of the polymer thin films increases as the degree of backbone fluorination increases, in a trend consistent with density functional theory calculations of the dipole moment.

We demonstrate proof-of-concept refractive-index structures with large refractive-index-gradient profiles, using a micro-contact photothermal annealing (CPA) process to pattern organic/inorganic hybrid materials comprising titanium oxide hydrate within a poly(vinyl alcohol) binder....

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