The interlayer waveguide grating coupling efficiencies under angular (rotational) misalignments are simulated using the 3D rigorous coupled-wave analysis (3D-RCWA) together with the RCWA equivalent-index-slab (RCWA-EIS) method. As examples of conical diffraction, rotations about the two coordinate axes, x and z, defined by the vectors [1 0 0] and [0 0 1], respectively, as well as an arbitrary a...

Phase gratings have been shown to produce electron beams with orbital angular momentum as demonstrated by numerous groups, and show promise for electron magnetic circular dichroism (EMCD) at the atomic scale [1, 2]. A linear diffraction grating will produce diffracted beams with a separation determined by the pitch or spacing between grating lines. A grating with a central line that forks into ...

In the previous experiment diffraction and interference were discussed and at the end a diffraction grating was introduced. In this lab most of the things learned in the last experiment will be applied to measure the wavelengths of the lines in the visible spectrum of some elements. You will use a diffraction grating mounted on a spectrometer to measure the interference maxima for various wavel...

Rigorous coupled-wave analysis (also called the Fourier-modal method) is an efficient tool for the numerical analysis of grating diffraction problems. We show that, with only a few modifications, this method can be used efficiently for the numerical analysis of aperiodic diffraction problems, including photonic crystal waveguides, Bragg mirrors, and grating couplers. We thus extend the domain o...

We discuss the applicability of holographically recorded gratings in photopolymers and holographic polymer-dispersed liquid crystals as neutron optical elements. An experimental investigation of their properties for light and neutrons with different grating spacings and grating thicknesses is performed. The angular dependencies of the diffraction efficiencies for those gratings are interpreted ...

A new approach is developed to calculate diffraction efficiency for a dielectric grating with an arbitrary refractive index profile. By treating a one-dimensional grating as a segment of a virtual two-dimensional (2D) photonic crystal, we exploit a rigorous theory of photonic crystal refraction and calculate the diffraction efficiencies. We expand, analytically in many cases, the dielectric fun...

Reflective diffraction gratings enable novel optical configurations that simplify and improve laser interferometers. We have proposed an all-reflective grating interferometer that can be used in LISA type interferometers for space gravitational wave detection [1]. One configuration requires a highly polarization sensitive grating. We report on characterizations of a grating made atop high refle...

We discuss the applicability of holographically recorded gratings in photopolymers and holographic polymer-dispersed liquid crystals as neutron optical elements. An experimental investigation of their properties for light and neutrons with different grating spacings and grating thicknesses is performed. The angular dependencies of the diffraction efficiencies for those gratings are interpreted ...

Based on the modified Kogelnik diffraction efficiency equation, we study the diffraction intensity spectrum and the total diffraction efficiency of reflection volume holographic gratings in photorefractive media. Taking photorefractive LiNbO3 crystal as an example, the effect of the grating parameters and the pulse width on the diffraction properties is presented under the influence of crystal ...

The picosecond holographic grating generation and detection of ultrasonic waves are described. Two mechanisms, a heating mechanism and a stimulated Brillouin scattering mechanism, are described. These permit the generation of tunable ultrasonic waves in the MHz to GHz range. It is demonstrated that the two mechanisms can be distinguished by the distinct time dependences of the diffraction of a ...