In this paper, the enhanced optical transmission through a special type of aperture of a bowtie shape is investigated through near-field imaging and finite-difference numerical analysis. Under linear polarizations in two orthogonal directions, the optical near fields of the bowtie aperture and comparable square and rectangular apertures made in gold and chromium thin films are measured and comp...

In this paper we demonstrate the ability to fabricate fishnets by nanoimprinting directly into a pre-deposited three layer metal–dielectric–metal stack, enabling us to pattern large areas in two minutes. We have designed and fabricated two different fishnet structures of varying dimensions using this method and measured their resonant wavelengths in the near-infrared at 1.45 μm and 1.88 μm. An ...

A full wave spectral domain method of moment along with reciprocity theorem analysis of finite phased array of aperture coupled circular microstrip patch antennas is presented. Both the electric surface currents on the patches and the equivalent magnetic current on the apertures are considered. Results of reflection coefficient magnitude, active input impedance, active element gain, efficiency ...

We propose a planar, ultrathin, subwavelength spectral light separator that enables efficient, angularly robust, spatially coregistered decomposition of light into its spectral components. The device consists of a collection of spectrally tuned “meta-atoms” and achieves spectral selectivity by utilizing strong localized resonance supported by each individual meta-atom. The three-dimensional met...

This Letter features a new, scalable fabrication method and experimental characterization of glass-filled apertures exhibiting extraordinary transmission. These apertures are fabricated with sizes, aspect ratios, shapes, and side-wall profiles previously impossible to create. The fabrication method presented utilizes top-down lithography to etch silicon nanostructures. These nanostructures are ...

A noniterative method for retrieving the phase of a wave field from a diffraction intensity measurement in a coherent wave field is proposed. In this method, the phase can be calculated from analytic equations based on the properties of entire functions by use of Fourier transforms. This method requires only a single measurement of the intensity of a diffracted wave through an array filter of r...

Many high-energy lasers (HELs) have noncircular output apertures. Some are rectangular in shape with or without a central or noncentral (up to 30%) obscuration. However, most high-energy laser propagation codes (especially those developed for systems analysis) model the aperture as either an unobscured circle or as a circle with fixed (e.g., 10%) obscuration. We present a beam-quality/aperture-...

We developed the anatomic rectangular tunnel anterior cruciate ligament reconstruction (ART ACLR) with a bone-patellar tendon-bone graft to mimic fibre arrangement inside the native ACL via tunnels with smaller apertures. With a 10-mm-wide graft, the cross-sectional area of the tunnels of 50 mm2 in ART ACLR is less than that of 79 mm2 in a 10-mm round tunnel one. Because tunnel encroachment wou...

The design of irregular planar phased arrays (PAs) characterized by a highly-modular architecture is addressed. By exploiting the property self-replicating tile shapes, also known as rep-tiles, arising array layouts consist tiles having different sizes, but equal shape, all being generated assembling finite number smaller and congruent copies single elementary building-block. Towards this end, ...