We address two-dimensional (2D) waveguide arrays where light tunneling into neighboring waveguides may be effectively suppressed by an out-of-phase harmonic modulation of the refractive index in neighboring waveguides at suitable frequencies. Genuine 2D features, such as anisotropic diffraction engineering, diffraction-free propagation along selected directions in the transverse plane, and tunn...

In this work, ZnO/SiO2 nanoparticles were prepared using sol-gel method, and platinum particles were loaded on ZnO/SiO2 nanoparticles by photoreductive method. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The XRD patterns showed that the zinc oxide samples have a wurtzite structure (hexagonal phase...

We present the results of our work on developing fully integrated devices (photonic dicers) for reformatting multimode light to a diffraction limited pseudo-slit. These devices can be used to couple a seeing limited telescope point spread function to a spectrograph operating at the diffraction limit, thus potentially enabling compact, high-resolution spectrographs that are free of modal noise.

We present a simple model for understanding the perfect blaze for diffraction with echelle gratings. Littrow diffraction at grating profiles with rectangular apexangles implicates two pairs of counterpropagating light waves. The four waves show a rectangular pattern of interference fringes. Integer numbers of such fringes along both facets of a groove ensure perfect blazing with echelle gratings.

The diffraction of pulsed beams of light is formulated as an anomalously dispersive phenomenon. In a dispersive material, the effects of material group-velocity dispersion and diffraction on pulsed beam propagation can mutually cancel if the transverse profile of the pulse is suitably chosen.

Abstract The paper presents a theoretical model of light diffraction on multilayer PPM-LC structures. A numerical calculation the characteristics four-layer structures under influence external electrical action is also given. possibility controlling type selective response an electric field each layer structure shown.

Diffraction limits standard optical microscopy to a spatial resolution of about half the wavelength of light. We present novel microscopy techniques for imaging semiconductor materials and devices at better than diffraction-limited spatial resolution and observe previously inaccessible phenomena. We discuss the methods and results for Numerical Aperture Increasing Lens (NAIL) and Near-field Sca...

We study light propagation in nanoscale periodic structures composed of dielectric and metal in the visible range. We demonstrate that diffraction can be tailored both in magnitude and in sign by varying the geometric features of the waveguides. Diffraction management on a subwavelength scale is demonstrated by numerical solution of Maxwell equations in the frequency domain.

A comparison is made between rigorous numerical results and a recently proposed analytical method for modeling light diffraction by lamellar diffraction gratings. The conclusion is that the analytical model is quite restrained in its applicability and can be misleading in determining the behavior of the grating efficiencies.