We study super-resolution capability of liquid-immersed high refractive index (n~1.9–2.1) barium titanate glass
microspheres with diameters from several microns up to hundreds of microns. Imaging is provided in a conventional
upright microscope with the spheres placed in a contact position with various semiconductor and metallic
nanostructures. Using a commercial Blu-ray disk, we demonstrate an ability to discern 100 nm feature sizes which
cannot be resolved by conventional microscopy. Using silver nanowires with diameter about 100 nm, we
demonstrate ~1.7 times improvement in spatial resolution compared to conventional diffraction-limited far field
microscopy. Using two-dimensional nanoplasmonic arrays, we demonstrate high resolution imaging by using
objectives with surprisingly small numerical apertures. The last property is attractive for high-resolution imaging at
long working distances. This imaging technique can be used in biomedical microscopy, microfluidics, and
EGO is an evolutionary, data-adaptive algorithm which can be useful for optimization problems with expensive cost
functions. Many antenna design problems qualify since complex computational electromagnetics (CEM) simulations
can take significant resources. This makes evolutionary algorithms such as genetic algorithms (GA) or particle swarm
optimization (PSO) problematic since iterations of large populations are required. In this paper we discuss multiparameter
optimization of a wideband, single-element antenna over a metamaterial ground plane and the interfacing of
EGO (optimization) with a full-wave CEM simulation (cost function evaluation).
Free space microwave measurements are reported for a split ring and post type metamaterial which exhibits negative refraction in a frequency band between 13.5 and 14.5 GHz. Varying azimuthal angles and magnitudes are achieved by changing the polarization of the transmitter and receiver relative to each other and to the anisotropic axes of the material. The amplitude of the cross- polarized transmission has been measured at 50% of the co- polarization level. The maximum amplitude was achieved at a polarization angle of 20 degrees relative to the initial polarization. This polarization conversion indicates there are other losses besides ohmic losses.
Negative refraction and left-handed electromagnetism in a photonic crystal are demonstrated in waveguide and free space experiments at microwave frequencies. Precision control to achieve tailor-made refractive indices has been achieved. The negative refraction in these photonic crystals is shown to lead to imaging by a flat lens. We have also developed a generalized theory of flat lens imaging. These results promise potential applications in a variety of optical and microwave systems for communications and imaging.