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The Bragg diffraction of neutrons and x-rays are well-suited to the task of determining the distribution of magnetization in crystals. Applications of the two techniques proceed by contrasting observed intensities with intensities…

Strongly Correlated Electrons · Physics 2022-12-21 Stephen W. Lovesey

We introduce a new X-ray imaging technique to facilitate propagation-based phase contrast of large, centimeter-sized samples. The diffracted X-ray wavefield behind the sample is demagnified by asymmetric Bragg crystal optics, thereby…

In this work, a general theoretical framework is presented to explain the formation of the phase signal in an X-ray microscope integrated with a grating interferometer, which simultaneously enables the high spatial resolution imaging and…

Optics · Physics 2022-09-28 Jiecheng Yang , Yongshuai Ge , Dong Liang , Hairong Zheng

The interaction of Na atoms with a surface was probed by inserting a nanofabricated material grating into one arm of an atom interferometer (IFM). This technique permits a direct measurement of the change in phase and coherence of matter…

Atomic Physics · Physics 2009-11-11 John D. Perreault , Alexander D. Cronin

Phase-contrast imaging is an emerging technology that may increase the signal-difference-to-noise ratio in medical imaging. One of the most promising phase-contrast techniques is Talbot interferometry, which, combined with energy-sensitive…

We present a novel atom interferometer configuration that combines large momentum transfer with the enhancement of an optical resonator for the purpose of measuring gravitational strain in the horizontal directions. Using Bragg diffraction…

Diffraction gratings with high upward diffraction efficiency and large effective length are required for chip-scale light detection and ranging. In this paper, we propose a diffraction grating based on a multilayer silicon nitride…

We present a precision gravimeter based on coherent Bragg diffraction of freely falling cold atoms. Traditionally, atomic gravimeters have used stimulated Raman transitions to separate clouds in momentum space by driving transitions between…

Nanothermochromic diffraction gratings based on the metal-insulator transition of $\mathrm{VO_2}$ are fabricated by site-selective ion beam implantation in a $\mathrm{SiO_2}$ matrix. Gratings were defined either (i) directly by spatially…

Materials Science · Physics 2012-10-25 Johannes Zimmer , Achim Wixforth , Helmut Karl , Hubert J. Krenner

Diffraction experiments with holographic gratings recorded in SiO$_2$ nanoparticle-polymer composites have been carried out with slow neutrons. The influence of parameters such as nanoparticle concentration, grating thickness and grating…

We construct an electron optical system to investigate Bragg diffraction (the crystal lattice plane, $10^{-2}$-$10^{-3}$ rad) with the objective lens turned off by adjusting the current in the intermediate lenses. A crossover was located on…

Materials Science · Physics 2019-11-06 Hiroshi Nakajima , Atsuhiro Kotani , Ken Harada , Shigeo Mori

If cooled-down neutron stars have a thin atomic crystalline-iron crust, they must diffract X-rays of appropriate wavelength. If the diffracted beam is to be visible from Earth, the illuminating source must be very intense and near the…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Felipe J. Llanes-Estrada , Gaspar Moreno Navarro

The thesis 'Investigations to Improve Energy Resolution for Neutron Backscattering Spectrometers Using Ideal Crystals with Low Dynamic Width of the Reflection Curve' first introduces the concept of the neutron backscattering spectrometer…

Instrumentation and Detectors · Physics 2023-09-06 Klaus-Dieter Liß

We experimentally demonstrate the phase relations of 3-port gratings by investigating 3-port coupled Fabry-Perot cavities. Two different gratings which have the same 1st order diffraction efficiency but differ substantially in their 2nd…

Optics · Physics 2009-11-13 A. Bunkowski , O. Burmeister , K. Danzmann , R. Schnabel

Grating interferometer is a state of art x-ray imaging approach, which can simultaneously acquire information of x-ray attenuation, phase shift, and small angle scattering. This approach is very sensitive to micro-structural variation and…

Medical Physics · Physics 2015-09-21 Wenxiang Cong , Yan Xi , Ge Wang

Photosensitive materials with ever-improving properties are of great importance for optical and photonics applications. Additionally, they are extremely useful for designing components for neutron optical devices. We provide an overview on…

Dark-field contrast imaging with grating interferometers has proven to hold huge potential for numerous applications with X-rays and with neutrons conveying biology and medicine as well as engineering and magnetism, respectively. However, a…

Materials Science · Physics 2013-12-03 Markus Strobl

Propagation-based neutron phase-contrast tomography was demonstrated using the ISIS pulsed spallation source. The proof-of-concept tomogram with Paganin-type phase-retrieval filter applied exhibited an effective net boost of $23\pm 1$ in…

Image and Video Processing · Electrical Eng. & Systems 2023-07-31 David M. Paganin , Morten Sales , Peter M. Kadletz , Winfried Kockelmann , Mario A. Beltran , Henning F. Poulsen , Søren Schmidt

Bragg diffraction has been used in atom interferometers because it allows signal enhancement through multiphoton momentum transfer and suppression of systematics by not changing the internal state of atoms. Its multi-port nature, however,…

Atomic Physics · Physics 2016-11-21 Richard H Parker , Chenghui Yu , Brian Estey , Weicheng Zhong , Eric Huang , Holger Müller

For holographic gratings recorded in superparamagnetic nanoparticle-polymer composites the diffraction efficiency should -- next to grating spacing, nanoparticle concentration and grating thickness -- depend on the strength of an external…

Instrumentation and Detectors · Physics 2015-06-04 J. Klepp , I. Drevensek-Olenik , S. Gyergyek , C. Pruner , R. A. Rupp , M. Fally