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Related papers: Tomographic femtosecond X-ray diffractive imaging

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We develop a means for speckle-based phase imaging of the projected thickness of a single-material object, under the assumption of illumination by spatially random time-independent x-ray speckles. These speckles are generated by passing x…

In modern high-gain free-electron lasers, ultra-fast photon pulses designed for studying chemical, atomic and biological systems are generated from a serial of behaviors of high-brightness electron beam at the time-scale ranging from…

Accelerator Physics · Physics 2015-10-22 Guanglei Wang , Meng Zhang , Wei Zhang , Haixiao Deng , Xueming Yang

The radiation resulting from the uniform motion of a charged particle near a hemispheric bulge in a metal plane is considered. The description of the radiation process based on the method of images is developed for the case of…

Accelerator Physics · Physics 2018-02-26 V. V. Syshchenko , E. A. Larikova , Yu. P. Gladkih

We derive the analytical theory describing the process of sub-femtosecond pulse formation from a quasi-monochromatic seeding extreme ultraviolet (XUV) radiation, which propagates in active medium of a hydrogen-like plasma-based X-ray laser…

We derive the distribution of flux density of a compact source exhibiting strong diffractive scintillation. Our treatment accounts for arbitrary spectral averaging, spatially-extended source emission, and the possibility of intrinsic…

Instrumentation and Methods for Astrophysics · Physics 2012-08-09 Michael D. Johnson , Carl R. Gwinn

X-ray absorption spectroscopy (XAS) is a powerful and well established technique with sensitivity to elemental and chemical composition. Despite these advantages, its implementation has not kept pace with the development of ultrafast pulsed…

We report the development of a fast rotating target to produce ultrashort incoherent X-ray pulses from bremsstrahlung. These short X-ray pulses are produced in the laser-plasma interaction of a 35 fs, 1 mJ pulse of a Ti:Sa laser of 1 kHz…

Instrumentation and Detectors · Physics 2018-09-26 Lucia Martín , José Benlliure , Dolores Cortina , Juan Llerena , David González , Camilo Ruiz

We present a new variant of dispersion scan (d-scan) based on surface third-harmonic generation (STHG) and a ptychographic algorithm taylored for full retrieval (amplitude and phase) of broadband laser pulses. We demonstrate the technique…

Optics · Physics 2022-10-10 Tiago Gomes , Miguel Canhota , Helder Crespo

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical…

Quantum Physics · Physics 2015-05-19 O. Firstenberg , P. London , D. Yankelev , R. Pugatch , M. Shuker , N. Davidson

We propose a complete pipeline that allows object detection and simultaneously estimate the pose of these multiple object instances using just a single image. A novel "keypoint regression" scheme with a cross-ratio term is introduced that…

Computer Vision and Pattern Recognition · Computer Science 2018-09-28 Ankit Dhall

Femtosecond-scale ultrafast imaging is an essential tool for visualizing ultrafast dynamics in molecular biology, physical chemistry, atomic physics, and fluid dynamics. Pump-probe imaging and a streak camera are the most widely used…

Optics · Physics 2020-03-18 Jungho Moon , Seok-Chan Yoon , Yong-sik Lim , Wonshik Choi

Based on the similarity of paraxial diffraction and dispersion mathematical descriptions, the temporal imaging of optical pulses combines linear dispersive filters and quadratic phase modulations operating as time lenses. We consider…

We present a novel, straightforward method for spatiotemporal characterization of ultra-short laser pulses. The method employs far-field interferometry and inverse Fourier transform spectroscopy, built on the theoretical basis derived in…

X-ray dark-field or ultra-small angle scatter imaging has become increasingly important since the introduction of phase-based x-ray imaging and is having transformative impact in fields such as in vivo lung imaging and explosives detection.…

Multiphoton microscopes employ femtosecond lasers as light sources because the high peak power of the ultrashort pulse allows for multiphoton excitation of fluorescence in the examined sample. However, such short pulses are susceptible to…

Optics · Physics 2024-08-13 Katarzyna Kunio , Jakub Bogusławski , Grzegorz Soboń

Because of their high photon flux, X-ray free-electron lasers (FEL) allow to resolve the structure of individual nanoparticles via coherent diffractive imaging (CDI) within a single X-ray pulse. Since the inevitable rapid destruction of the…

We demonstrate a novel, single-shot ultrafast diagnostic, based on the dispersion-scan (d-scan) technique. In this implementation, rather than scanning wedges to vary the dispersion as in standard d-scan, the pulse to be measured…

Semiconductor lasers offer native bifunctionality enabling coherent light emission and linear photodetection. They can also operate as sensitive two-photon absorption detectors due to the third-order nonlinearity of the heterostructure…

The formation of relativistic electron mirror produced via ionization of thin solid target by ultraintense femtosecond laser pulse is considered with the help of computer simulations. It is shown that the reflection of weak…

Plasma Physics · Physics 2007-05-23 Vladimir A. Cherepenin , Victor V. Kulagin

Saturable absorption is a nonlinear effect where a material's ability to absorb light is frustrated due to a high influx of photons and the creation of electron vacancies. Experimentally induced saturable absorption in copper revealed a…