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We demonstrate a method to image an object using a self-probing approach based on semiconductor high-harmonic generation. On one hand, ptychography enables high-resolution imaging from the coherent light diffracted by an object. On the…

Near-field optical microscopy can be used as a viable route to understand the nanoscale material properties below the diffraction limit. On the other hand, atomically thin two-dimensional (2D) transition metal dichalcogenides (TMDs) are the…

We show that an arbitrary spatial distribution of complex refractive index inside an object can be exactly represented as a sum of two "monomorphous" complex distributions, i.e. the distributions with the ratios of the real part to the…

Medical Physics · Physics 2015-12-09 T. E. Gureyev , Ya. I. Nesterets

With the growing technology of photon-counting detectors (PCD), spectral CT is a widely concerned topic which has the potential of material differentiation. However, due to some non-ideal factors such as cross talk and pulse pile-up of the…

Medical Physics · Physics 2020-07-21 Ao Zheng , Hongkai Yang , Li Zhang , Yuxiang Xing

We report a new theoretical method for X-ray absorption spectroscopy (XAS) in condensed matter which is based on the multi-channel multiple scattering theory of Natoli et al. and the eigen-channel R-matrix method. While the highly flexible…

Materials Science · Physics 2009-11-10 Peter Krüger , Calogero R. Natoli

Three different approaches have been proposed so far for production of highly monochromatic X-rays from a baseline XFEL undulator: (i) single-bunch self-seeding scheme with a four crystal monochromator in Bragg reflection geometry; (ii)…

Accelerator Physics · Physics 2010-06-11 Gianluca Geloni , Vitali Kocharyan , Evgeni Saldin

X-ray interaction with matter is an energy-dependent process that is contingent on the atomic structure of the constituent material elements. The most advanced models to capture this relationship currently rely on Monte Carlo (MC)…

Machine Learning · Computer Science 2023-07-11 Raziye Kubra Kumrular , Thomas Blumensath

An ab initio theory is devised for the x-ray photoabsorption cross section of atoms in the field of a moderately intense optical laser (800nm, 10^13 W/cm^2). The laser dresses the core-excited atomic states, which introduces a dependence of…

Atomic Physics · Physics 2013-03-25 Christian Buth , Robin Santra

Correlative microscopy is a powerful technique that combines the advantages of multiple imaging modalities to achieve a comprehensive understanding of investigated samples. For example, fluorescence microscopy provides unique functional…

Due to the low X-ray photon utilization efficiency and low measurement sensitivity of the electron multiplying charge coupled device (EMCCD) camera setup, the collimator based narrow beam X-ray luminescence computed tomography (XLCT)…

Medical Physics · Physics 2018-03-14 Wei Zhang , Michael C Lun , Alex Anh-Tu Nguyen , Changqing Li

X-ray near field holography has proven to be a powerful 2D and 3D imaging technique with applications ranging from biomedical research to material sciences. To reconstruct meaningful and quantitative images from the measurement intensities,…

Image and Video Processing · Electrical Eng. & Systems 2024-03-04 Jens Lucht , Leon M. Lohse , Thorsten Hohage , Tim Salditt

In a three-level atomic system coupled by two equal-amplitude laser fields with a frequency separation 2$\delta$, a weak probe field exhibits a multiple-peaked absorption spectrum with a constant peak separation $\delta$. The corresponding…

Quantum Physics · Physics 2009-11-10 J. Wang , Yifu Zhu , K. J. Jiang , M. S. Zhan

While it is well known that X-ray tomography using a polychromatic source is non-linear, as the linear attenuation coefficient depends on the wavelength of the X-rays, tomography using near monochromatic sources are usually assumed to be a…

Instrumentation and Detectors · Physics 2017-05-16 William R. B. Lionheart , Bjørn Tore Hjertaker , Rachid Maad , Ilker Meric , Sophia B. Coban , Geir Anton Johansen

The grand canonical Monte Carlo method is employed to study the adsorption of Xe on a quasicrystalline Al-Ni-Co surface. The calculation uses a semiempirical gas-surface interaction, based on conventional combining rules and the usual…

Soft Condensed Matter · Physics 2009-11-11 Wahyu Setyawan , Nicola Ferralis , Renee D. Diehl , Milton W. Cole , Stefano Curtarolo

We demonstrate the use of a phase retrieval technique for propagation-based phase contrast neutron imaging with a polychromatic beam. This enables imaging samples with low absorption contrast and/or improving the signal-to-noise ratio to…

Atomic-resolution imaging with scanning transmission electron microscopy is a powerful tool for characterizing the nanoscale structure of materials, in particular features such as defects, local strains, and symmetry-breaking distortions.…

X-ray Absorption Near Edge Structure [XANES] of FePt nanoclusters has been studied using a full multiple scattering, self-consistent field [SCF], real-space Green`s function approach realized via the powerful ab initio FEFF8 code. One…

Materials Science · Physics 2009-11-10 Sher Alam , J. Ahmed , Y. Matsui

Shadow X-ray Magnetic Circular Dichroism Photo-Emission Electron Microscopy (XMCD-PEEM) is a recent technique, in which the photon intensity in the shadow of an object lying on a surface, may be used to gather information about the…

We introduce a method to experimentally measure the monochromatic transmission matrix of a complex medium in optics. This method is based on a spatial phase modulator together with a full-field interferometric measurement on a camera. We…

Optics · Physics 2010-03-10 S. M. Popoff , G. Lerosey , R. Carminati , M. Fink , A. C. Boccara , S. Gigan

We describe a feasible implementation of a novel X-ray detector for highly energetic x-ray photons with a large solid angle coverage, optimal for the detection of Compton x-ray scattered photons. The device consists of a 20~cm-thick…

Instrumentation and Detectors · Physics 2022-01-27 Ángela Saá Hernández , Diego González-Díaz , Pablo Villanueva , Carlos Azevedo , Marcos Seoane