The first microstructured polymer optical fibre is described. Both experimental and theoretical evidence is presented to establish that the fibre is effectively single moded at optical wavelengths. Polymer-based microstructured optical fibres offer key advantages over both conventional polymer optical fibres and glass microstructured fibres. The low-cost manufacturability and the chemical flexibility of the polymers provide great potential for applications in data communication networks and for the development of a range of new polymer-based fibre-optic components.

Using conventional materials, the resolution of focusing and imaging devices is limited by diffraction to about half the wavelength of light, as high spatial frequencies do not propagate in isotropic materials. Wire array metamaterials, because of their extreme anisotropy, can beat this limit; however, focusing with these has only been demonstrated up to microwave frequencies and using propagation over a few wavelengths only. Here we show that the principle can be scaled to frequencies orders of magnitudes higher and to considerably longer propagation lengths. We demonstrate imaging through straight and tapered wire arrays operating in the terahertz spectrum, with unprecedented propagation of near field information over hundreds of wavelengths and focusing down to 1/28 of the wavelength with a net increase in power density. Applications could include in vivo terahertz-endoscopes with resolution compatible with imaging individual cells.

The authors report what is, to their knowledge, the highest electro-optic effect measured in a germanosilicate fibre ever reported. The electro-optic effect based on a permanent second-order nonlinearity has been induced by UV-excited poling at 193 nm with an electric field > 8 × 10⁵ V/cm. Polarisation dependence of the V_πL product in a birefringent fibre has been observed, and the lowest V_πL product obtained for the TE mode of 32 Vcm, comparable to that based on r₂₂ of LiNbO₃, has been measured at 633 nm with a phase modulation at frequencies up to 5 MHz.

Electromagnetic metamaterials attract much attention since they can be engineered to exhibit optical properties not found in nature. Their fabrication, however, is challenging, especially in volume. We introduce drawing as a means of fabricating metamaterials, thus demonstrating a terahertz metamaterial. We codraw polymethyl-methacrylate and indium, producing several meters of metamaterial with wire diameters down to $\sim 10\mu \text{m}$ , and lattice constants of $\sim 100\mu \text{m}$ . We experimentally characterize the transmission properties of different samples, observing high-pass filtering between 0.3–0.4 THz, in good agreement with simulations.