With advances in nanotechnology, emerging plasmonic nano-optical applications, such as all-optical magnetic recording, require circularly-polarized electromagnetic radiation beyond the diffraction limit. In this study, a plasmonic cross-dipole nano-antenna is investigated to obtain a circularly polarized near-field optical spot with a size smaller than the diffraction limit of light. The perfor...

The generation of a sub-diffraction optical hollow ring is of great interest in various applications, such as optical microscopy, optical tweezers, and nanolithography. Azimuthally polarized light is a good candidate for creating an optical hollow ring structure. Various of methods have been proposed theoretically for generation of sub-wavelength hollow ring by focusing azimuthally polarized li...

We discuss the possibility of light control by means of light diffraction by space charge waves which are the periodic domain trains induced at some circumstances in GaAs Gunn effect diode. The two possible regimes of the proposed device are considered: the first one which is analogous to the Bragg diffraction in case of light-acoustic diffraction and the other one, which we call “intermediate”...

We present a new wave-vector-space approach for solving inverse scattering problems. In our formulation, the theories for diffraction tomography and coherence gating are combined to explain 3D reconstruction with low-coherence light. Specifically, we apply this method to solve the scattering problem with broadband fields for transmission and reflection measurements. Our results can be applied t...

We have investigated the causes of low efficiency for optical beam steering devices based on liquid crystal decentered microlens arrays (DLAs). We show that the efficiency is effected by the relative phase of light exiting the individual lenses, the imperfect focusing of small lenses due to diffraction, the aberrations related to off-axis light going through a lens, and the diffraction spreadin...

We have made a diffraction grating in an indoline azobenzene/amorphous polycarbonate film by two-beam interference at 532 nm that periodically photodegrades the indoline azobenzene dye. Subsequent illumination of the film with 532-nm light into the trans-isomer band leads to trans-cis isomerization in the indoline azobenzene dye and results in a decrease in the trans-isomer band absorption coef...

The generation of a sub-diffraction longitudinally polarized spot is of great interest in various applications, such as optical tweezers, super-resolution microscopy, high-resolution Raman spectroscopy, and high-density optical data storage. Many theoretical investigations have been conducted into the tight focusing of a longitudinally polarized spot with high-numerical-aperture aplanatic lense...

We describe a new biosensor immunoassay involving optical diffraction to detect clinically Important analytes in human body fluids. A siliconwafer is used as a support for immobilization of antigen or antibody. The protein-coated surface is illuminated through a photo mask to create distinct periodic areas of active and inactive protein. When the surface is incubated with a positive sample, ant...

The interpretation of the detection of very slow rate of photo counts in interference and diffraction experiments have given rise to the prevailing interpretation that photons interfere by themselves and they are indivisible, albeit non-local. The purpose of this paper is to inspire the development of alternate models for the photons by underscoring that, in reality, light does not interfere wi...

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...