Recent progress in the development of holographic gratings for neutron-optics applications is reviewed. We summarize the properties of gratings recorded in deuterated (poly)methylmethacrylate, holographic polymer-dispersed liquid crystals and nanoparticle-polymer composites revealed by diffraction experiments with slow neutrons. Existing and anticipated neutron-optical instrumentations based on...

An atom-surface interaction was detected by studying atom diffraction from a rotated material grating. A phasor diagram similar to the Cornu spiral was developed to explain why there are no missing orders in atom diffraction from material gratings. We also show that atom-surface interactions combined with rotated grating structures can produce asymmetric, i.e., blazed, diffraction patterns. Our...

The diffraction efficiency behavior of reflection gratings with an asymmetrical trapezoidal groove profile has been studied. Theoretical calculations predict that at certain grating parameters superior efficiency compared to the conventional ruled gratings can be achieved.

The aptamer-functionalized hydrogel diffraction gratings were successfully fabricated by incorporating an aptamer and its complementary sequence as crosslinking junctions in the network structure. The gratings showed a sensitive response to human thrombin as read out from the diffracted light.

We present results on permanent gratings in highly dye-doped liquid crystal cells without polymer coatings of the cells' surfaces. The surface-mediated gratings remain in cells for months without degradation of their quality. The peak diffraction efficiency can be controlled, enhanced or decreased, by applying low voltage AC field. At low frequencies, below 1 Hz, the diffracted signal can modul...

Different electromagnetic theories have been applied in order to understand the interaction of the electromagnetic radiation with diffraction gratings. Kogelnik’s Coupled Wave Theory, for instance, has been applied with success to describe the diffraction properties of sinusoidal volume gratings. Nonetheless the predictions of Kogelnik’s theory deviate from the actual behaviour whenever the hol...

We report the growth and characterization of a new photorefractive material, potassium lithium tantalate niobate (KLTN). A KLTN crystal doped with copper is demonstrated to yield high diffraction efficiency of photorefractive gratings in the paraelectric phase. Voltage-controllable index gratings with n(1) = 8.5 x 10(-5) were achieved, which yielded diffraction efficiencies of 75% in a 2.9-mm-t...

We have demonstrated the use of a high-repetition-rate 46.9-nm tabletop laser to characterize diffraction gratings designed for grazing-incidence operation in the soft-x-ray spectral region. The efficiencies for various diffraction orders were measured as a function of angle of incidence and compared with the results of model simulations. This measurement technique provides benchmarks with whic...

A detailed analysis of anomalies of metallic gratings is performed for a large interval of groove depths. Two types of zero of the zeroth diffraction order are distinguished: the Bragg type [Alta Freq. 38, 82 (1969)], exhibited in a Littrow mount for both TM and TE polarizations and localized for flat surfaces at negative imaginary infinity in the complex a plane of the sinus of angles of incid...

We have studied the optical properties of electrically switched holographic gratings fabricated using polymer-dispersed liquid crystal (PDLC) materials. We have found that the PDLC mixture can be used to control the diffractive properties of the composite gratings, including the anisotropy of the grating. 2000 Optical Society of America OCIS codes: (050.0050) Diffraction and gratings, (050.733...