Related papers: Neutral Helium Atom Diffraction from a Micron Scal…
We experimentally and theoretically studied a new left-handed (LH) structure based on a photonic crystal (PC) with a negative refractive index. The structure consists of triangular array of rectangular dielectric bars with dielectric…
Diffraction patterns of electrons are believed to resemble those of electromagnetic waves (EMW). I performed a series of experiments invoked to show that the periodicity of peaks in the diffraction diagram of electrons is concerned with the…
Hafnium hydride is a promising material for next-generation nuclear reactors, particularly as control rods for fast fission and shielding in fusion systems. The material's intrinsic brittleness encourages its use in the form of…
We have studied the small scale distribution of atomic hydrogen (HI) using 21-cm absorption spectra against multiple-component background radio continuum sources from the 21-SPONGE survey and the Millennium Arecibo Absorption Line Survey.…
The PhD thesis is devoted to the study of second harmonic generation of narrow beams in photonic crystals. The basic idea is that if both frequencies, the fundamental and second harmonics are in the region of self-collimation, then the…
Neutrons have emerged as a unique probe at the forefront of modern material science, unrivaled in their penetrating abilities. A major challenge stems from the fact that neutron optical devices are limited to refractive indices on the order…
We demonstrate a neutron tomography technique with sub-micrometer spatial resolution. Our method consists of measuring neutron diffraction spectra using a double crystal diffractometer as a function of sample rotation and then using a phase…
We carried out synthetic observations of interstellar atomic hydrogen at 21cm wavelength by utilizing the magneto-hydrodynamical numerical simulations of the inhomogeneous turbulent interstellar medium (ISM) Inoue and Inutsuka (2012). The…
Using the Fisher information (FI), the design of neutron reflectometry experiments can be optimised, leading to greater confidence in parameters of interest and better use of experimental time [Durant, Wilkins, Butler, & Cooper (2021). J.…
We observe light-induced frequency shifts in one-color photoassociative spectra of magnetically trapped $^4$He$^*$ atoms in the metastable $2^3S_1$ state. A pair of ultracold spin-polarized $2^3S_1$ helium atoms is excited into a molecular…
Plane-wave electrons undergo momentum transfer as they scatter off a target in overlapping spherical waves. The transferred momentum leads to target structural information to be encoded in angle and energy differential scattering. For…
We propose a method to increase both the neutron storage time and the precision of its lifetime measurements by at least tenfold. The storage of ultracold neutrons (UCN) in material traps now provides the most accurate measurements of…
We report on the fabrication of what we believe is the first example of a two dimensional nonlinear periodic crystal\cite{berger}, where the refractive index is constant but in which the 2nd order nonlinear susceptibility is spatially…
It is shown that rough inner walls of a trap of ultracold neutrons can be coated with a superfluid helium film much thicker than the depth of penetration of ultracold neutrons into helium. This coating should reduce the rate of loss of…
Optical transition radiation interferometry (OTRI) has been shown to be a very useful technique to measure the divergence of electron beams with energies in the range of 15-100 MeV. However, application of this method to low energy or very…
In recent years the interest in studying interactions of Rydberg atoms or ensembles thereof with optical and microwave frequency fields has steadily increased, both in the context of basic research and for potential applications in quantum…
We report on a recent paper (Wei\ss\ \& Buchert 1993), where we carry out pencil beam constructions in a high-resolution simulation of the large-scale structure of galaxies. As an example we present the results for the case of…
Optical methods are most convenient to analyze spatially periodic patterns with wavevector $\bm q$ in a thin layer of a nematic liquid crystal. In the standard experimental setup a beam of parallel light with a 'short' wavelength $\lambda…
In this paper we implement experimentally the spatial shape modelling of nondiffracting optical beams via computer generated holograms. The results reported here are the experimental confirmation of the so called Frozen Wave method,…
The initial demonstrations over the last several years of the use of optical diffraction radiation (ODR) as non-intercepting electron-beam-parameter monitors are reviewed. Developments in both far-field imaging and near-field imaging are…