We experimentally demonstrate a planar metamaterial analogue of electromagnetically induced transparency at optical frequencies. The structure consists of an optically bright dipole antenna and an optically dark quadrupole antenna, which are cut-out structures in a thin gold film. A pronounced coupling-induced reflectance peak is observed within a broad resonance spectrum. A metamaterial sensor based on these coupling effects is experimentally demonstrated and yields a sensitivity of 588 nm/RIU and a figure of merit of 3.8.

A significant challenge to the wide utilization of X-ray microscopy lies in the difficulty in fabricating adequate high-resolution optics. To date, electron beam lithography has been the dominant technique for the fabrication of diffractive focusing optics called Fresnel zone plates (FZP), even though this preparation method is usually very complicated and is composed of many fabrication steps. In this work, we demonstrate an alternative method that allows the direct, simple, and fast fabrication of FZPs using focused Ga(+) beam lithography practically, in a single step. This method enabled us to prepare a high-resolution FZP in less than 13 min. The performance of the FZP was evaluated in a scanning transmission soft X-ray microscope where nanostructures as small as sub-29 nm in width were clearly resolved, with an ultimate cutoff resolution of 24.25 nm, demonstrating the highest first-order resolution for any FZP fabricated by the ion beam lithography technique. This rapid and simple fabrication scheme illustrates the capabilities and the potential of direct ion beam lithography (IBL) and is expected to increase the accessibility of high-resolution optics to a wider community of researchers working on soft X-ray and extreme ultraviolet microscopy using synchrotron radiation and advanced laboratory sources.

A deep ultraviolet off-axis digital holographic microscope (DHM) is presented. The microscope has been arranged with as least as possible optical elements in the imaging path to avoid aberration due to the non-perfect optical elements. A high resolution approach has been implemented in the setup using oblique illumination to overcome the limitation introduced by the optical system. To examine the resolution of the system a nano-structured template has been designed and the result confirms the submicron and nanoscale resolution of the arranged DHM setup.

Semiconductor/metal radial superlattices are produced by the roll-up of inherently strained InGaAs∕Ti∕Au as well as InAlGaAs∕GaAs∕Cr films. Cross sections of the obtained structures are prepared and investigated in detail by diverse transmission electron microscopy as well as microanalysis techniques. Special attention is paid to the interfaces of the semiconductor/metal hybrid superlattice. The study reveals amorphous, noncrystalline layers for the semiconductor/metal as well as for the metal/semiconductor interface. The chemical analysis suggests that the observed interlayers are oxides giving rise to a semiconductor/oxide/metal/oxide superlattice rather than a pure semiconductor/metal superlattice.