Download or read book High Harmonic Generation for Coherent Diffractive Imaging written by Sven Teichmann and published by LAP Lambert Academic Publishing. This book was released on 2010-09 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sven Teichmann s doctorate features experimental work on a high-harmonic generation source and coherent diffractive imaging. High-harmonic generation allows generating coherent and laser-like extreme- ultraviolet and soft x-ray radiation based on the frequency-upconversion of laser light. A novel and successful approach of employing harmonic emission that consists of multiple harmonic orders is presented. This emission is utilized for coherent diffractive imaging by illuminating a sample of unknown structure, e.g. a membrane protein. The diffractive image of that sample is then processed by means of computational algorithms and the structure of the sample can be recovered. This innovative work of a very high level of technical achievement is considered as internationally significant by world leaders in the field of high- harmonic generation and may prove valuable particularly for time-resolved spectroscopy, sources of soft x-ray and extreme-ultraviolet radiation, and imaging based on harmonic emission.

Download or read book Nanoscale Coherent Diffractive Imaging Using High harmonic XUV Sources written by Getnet Tadesse and published by . This book was released on 2019* with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Imaging using sources in the XUV and X-ray spectral range combines high resolution with longer penetration depth (compared to electron/ion microscopy) and found applications in many areas of science and technology. Coherent diffractive imaging (CDI) techniques, in addition, lift the performance limitation of conventional XUV/X-ray microscopes imposed by image forming optics and enable diffraction limited resolutions. Until recently, CDI techniques were mainly confined to large scale facilities e.g. synchrotrons and X-ray free electron lasers due to unavailability of suitable table-top XUV/X-ray sources. Table-top sources based on high-order harmonic generation (HHG) nowadays offer high and coherent photon flux which widened the accessibility of CDI techniques. So far, table-top CDI systems were not able to resolve sub-100 nm features using performance metrics that can qualify these systems for real world applications. In this work, CDI experiments with the highest resolutions in different modalities using a high flux fiber laser driven HHG source are presented. In conventional CDI, a record-high resolution of 13 nm is demonstrated together with the possibility of high speed acquisition with sub-30 nm resolution. In a holographic implementation of CDI, features with a half-distance of 23 nm are resolved which are the smallest features to ever be resolved with a table-top XUV/X-ray imaging system. Ptychographic imaging of extended samples is also performed using a reliable Rayleigh-like resolution metric and resolving of features as small as 2.5 wavelengths is demonstrated. These systems can find applications in material and biological sciences, study of ultrafast dynamics, imaging of semiconductor structures and EUV lithographic mask inspection.

Download or read book Nanoscale Waveguiding Studied by Lensless Coherent Diffractive Imaging Using EUV High Harmonic Generation Source written by Sergey Zayko and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The challenge of nanometric imaging drives intense efforts in applied sciences and fundamental research. Following the physical law of diffraction, the utilization of extreme ultraviolet (EUV) or X-ray radiation for imaging extends the ultimate resolution limit given by the illumination wavelength down to nanoscale dimensions. However, despite the great potential, the resolution is governed by imperfections inherent to optical elements employed. In this cumulative thesis, a table-top source of EUV radiation based on high harmonic generation (HHG), is developed and applied for lensless coher...

Download or read book Coherent EUV Light from High order Harmonic Generation Enhancement and Applications to Lensless Diffractive Imaging written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Coherent EUV light from high-order harmonic generation: Enhancement and applications to lensless diffractive imaging.

Download or read book Extreme Ultraviolet Hyperspectral Coherent Diffractive Imaging written by Meng Yijian and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We demonstrate hyperspectral imaging using two time-delayed, coherent extreme ultraviolet (XUV) sources. The approach combines broadband XUV high-harmonic generation, holographic imaging, and Fourier transform spectroscopy. The two harmonics sources are spatially separated at generation, and overlap in the far field resulting in a double slit diffraction pattern. We record the two-dimensional intensity modulation as a function of relative time delay; the Fourier transform determines the spatially dependent spectrum. To reduce the delay jitter and improve the spectral resolution, we demonstrate a novel experimental setup that records the relative delay of the two pulses through optical interference. Moreover, we have demonstrated that this broadband approach can be extended to Fourier transform holographic imaging, which avoids extensive phase retrieval computations. Applications include imaging of biological materials near the carbon K-edge.

Download or read book Lensless Imaging with High harmonic Sources written by and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coherent diffractive imaging (CDI) is a family of computational imaging techniques that uses iterative reconstruction algorithms to decipher the information encoded in one or more interference patterns to reconstruct an image of an object located in another propagation plane. The lensless nature of these techniques makes them well-suited for imaging with coherent extreme ultraviolet (EUV) or x-ray illumination as refractive optics are limited at these wavelengths. In particular, this work investigates the use of CDI techniques in combination with high-harmonic generation. High-harmonic generation~(HHG) sources can generate EUV illumination beams with a high degree of spatial coherence in a compact tabletop setup. In this work we use Fourier-Transform spectroscopy~(FTS) to separate sets of nearly monochromatic diffraction patterns from a broadband HHG diffraction pattern. These monochromatic diffraction patterns can used to reconstruct spectrally resolved images through reconstruction methods that are similar to those applied in conventional CDI. In Chapter 4 we describe how we use a common path interferometer and a noncollinear chirped pulse amplifier system to generate phase locked 25 fs pulse pairs with a central wavelength of approximately 800 nm and a combined pulse energy of 10 mJ. These infrared driving laser pulses are focused at slightly separated locations in a noble gas jet to upconvert them into a pair of almost identical high-harmonic pulses. In FTS-based imaging experiments, we illuminate a sample with the HHG pulse pairs and record the far-field diffraction pattern as a function of pulse-to-pulse time delay. The spatial separation of our two harmonic beams results in spatial interference between two laterally sheared copies of the diffraction pattern. As a consequence of the geometry, the spectrally separated diffraction patterns obtained in these measurements are similar, but not identical to the standard CDI case. In this work, we demonstrated an algorithm, called diffractive shear interferometry (DSI), to reconstruct images from such diffraction patterns. Using this algorithm, the information present in these diffraction patterns is used to reconstruct complex images of the sample. The reverse problem is either constrained by combining an diffraction pattern with a finite object support prior in Chapter 5 or with other diffraction patterns with a different relative orientation between the shear and the object. One of the advantages of coherent diffractive imaging techniques is that it they reconstruct the full complex electric field at the sample. In reflection mode, such phase difference can be easily attributed to height differences of the reflecting surface. However, most research in diffractive imaging has focused on transmission mode imaging. At the EUV wavelengths generated by HHG sources normal incidence reflection coefficients are vanishingly small. However towards grazing incidence the reflection coefficients approach one. Such a geometry does come at a cost of added experimental and computational complexity. While far-field diffraction between colinear planes can be described by a straight forward Fourier transform of the electric field, for the propagation between non-collinear planes, an additional non-linear coordinate transformation is required. This coordinate transformation depends on the tilt angle of the fields and becomes very sensitive to the exact tilt-angle towards grazing incidence. While CDI itself requires accurate knowledge of the wave propagation, a technique known as ptychography offers more flexibility, as it is often possible to solve for more variables than just the object field. In Chapter 7 we use that property to demonstrate an auto-calibration algorithm that can iteratively calibrate the tilt-angle during a ptychographic reconstruction. Using this approach we were able to refine the tilt angle close to the correct value even when the initial estimates were off by more than 5 degrees, greatly improving flexibility in reflection-mode lensless imaging.

Download or read book Nanoscale Photonic Imaging written by Tim Salditt and published by Springer Nature. This book was released on 2020-06-09 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book, edited and authored by a team of world-leading researchers, provides a broad overview of advanced photonic methods for nanoscale visualization, as well as describing a range of fascinating in-depth studies. Introductory chapters cover the most relevant physics and basic methods that young researchers need to master in order to work effectively in the field of nanoscale photonic imaging, from physical first principles, to instrumentation, to mathematical foundations of imaging and data analysis. Subsequent chapters demonstrate how these cutting edge methods are applied to a variety of systems, including complex fluids and biomolecular systems, for visualizing their structure and dynamics, in space and on timescales extending over many orders of magnitude down to the femtosecond range. Progress in nanoscale photonic imaging in Göttingen has been the sum total of more than a decade of work by a wide range of scientists and mathematicians across disciplines, working together in a vibrant collaboration of a kind rarely matched. This volume presents the highlights of their research achievements and serves as a record of the unique and remarkable constellation of contributors, as well as looking ahead at the future prospects in this field. It will serve not only as a useful reference for experienced researchers but also as a valuable point of entry for newcomers.

Download or read book Generation and Application of Coherent Extreme Ultraviolet Radiation written by Hoang Vu Le and published by LAP Lambert Academic Publishing. This book was released on 2015-06-29 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: High harmonic generation featuring ultra-short pulses, short wavelengths and highly coherent radiation in a table-top setup has become one of the most versatile and affordable tools for studies of atomic and molecular dynamics as well as for nano-scale coherent diffractive imaging. In this book, we show the background and technical aspects of the generation and enhancement of high order harmonic radiations down to the water window region (2.3 - 4.4 nm). The source is specifically tailored and developed for imaging applications. By controlling and stabilizing the phase-matching condition in a gas cell, an extreme ultra-violet source which satisfies these requirements has been generated. Using a harmonic source with wavelengths around 30 nm, a resolution of 45 nm for a micrometer-size transmission sample has been obtained and biological-like absorption samples are also successfully reconstructed. A phase retrieval algorithm with a phase-curvature correction is developed to take advantage of the higher photon flux when placing the sample near the focus point.

Download or read book Coherent Diffraction Imaging Using a High Harmonic Source at 40 EV written by Aaron D. Parsons and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Second Harmonic Generation Imaging written by Francesco S. Pavone and published by Taylor & Francis. This book was released on 2016-04-19 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Second-harmonic generation (SHG) microscopy has shown great promise for imaging live cells and tissues, with applications in basic science, medical research, and tissue engineering. Second Harmonic Generation Imaging offers a complete guide to this optical modality, from basic principles, instrumentation, methods, and image analysis to biomedical a

Download or read book Deep Neural Networks for Classifying Complex Features in Diffraction Images written by Julian Zimmermann and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Intense short-wavelength pulses from free-electron lasers and high-harmonic-generation sources enable diffractive imaging of individual nanosized objects with a single x-ray laser shot. The enormous data sets with up to several million diffraction patterns present a severe problem for data analysis because of the high dimensionality of imaging data. Feature recognition and selection is a crucial step to reduce the dimensionality. Usually, custom-made algorithms are developed at a considerable effort to approximate the particular features connected to an individual specimen, but because they face different experimental conditions, these approaches do not generalize well. On the other hand, deep neural networks are the principal instrument for today's revolution in automated image recognition, a development that has not been adapted to its full potential for data analysis in science. We recently published [Langbehn et al., Phys. Rev. Lett. 121, 255301 (2018)] the application of a deep neural network as a feature extractor for wide-angle diffraction images of helium nanodroplets. Here we present the setup, our modifications, and the training process of the deep neural network for diffraction image classification and its systematic bench marking. We find that deep neural networks significantly outperform previous attempts for sorting and classifying complex diffraction patterns and are a significant improvement for the much-needed assistance during postprocessing of large amounts of experimental coherent diffraction imaging data

Download or read book High Order Harmonics Generation in Plasmas written by Rashid A. Ganeev and published by Springer Nature. This book was released on 2022-08-01 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises a detailed consideration of novel approaches developed in the field of frequency conversion of laser sources in laser-induced plasmas during the last few years. The aim of the book is to support researchers and other readers in their development in the area of high-order nonlinear spectroscopy. Particularly, the advanced studies of nanoparticles and quantum dots for the formation of new sources of radiation in different short-wavelength spectral ranges show the ways to further implement the specific features of small-sized species in a relatively new field of study—laser ablation induced high-order harmonics generation spectroscopy. Researchers involved in the development of new methods of frequency conversion will benefit from finding the most recent advances in this field. Undergraduate students will discover interesting information about recent findings in plasma harmonic research. Additionally, the usefulness of the book will be demonstrated by the potential applications of the new knowledge developed during recent years for ultrafast pulse generation using the proposed schemes of plasma-light interaction. Thus, the audience may also include those researchers involved in state-of-the-art developments in attophysics. Additionally, any professionals interested in the application of the advanced techniques for material science will also benefit from updating their knowledge of new methods of material studies using high-order nonlinear spectroscopy.

Download or read book Structural Dynamics with X ray and Electron Scattering written by Kasra Amini and published by Royal Society of Chemistry. This book was released on 2023-12-20 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the early 20th century, X-ray and electron scattering has provided a powerful means by which the location of atoms can be identified in gas-phase molecules and condensed matter with sub-atomic spatial resolution. Scattering techniques can also provide valuable observables of the fundamental properties of electrons in matter such as an electron’s spin and its energy. In recent years, significant technological developments in both X-ray and electron scattering have paved the way to time-resolved analogues capable of capturing real-time snapshots of transient structures undergoing a photochemical reaction. Structural Dynamics with X-ray and Electron Scattering is a two-part book that firstly introduces the fundamental background to scattering theory and photochemical phenomena of interest. The second part discusses the latest advances and research results from the application of ultrafast scattering techniques to imaging the structure and dynamics of gas-phase molecules and condensed matter. This book aims to provide a unifying platform for X-ray and electron scattering.

Download or read book Optical Technologies for Extreme Ultraviolet and Soft X ray Coherent Sources written by Federico Canova and published by Springer. This book was released on 2015-08-17 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book reviews the most recent achievements in optical technologies for XUV and X-ray coherent sources. Particular attention is given to free-electron-laser facilities, but also to other sources available at present, such as synchrotrons, high-order laser harmonics and X-ray lasers. The optical technologies relevant to each type of source are discussed. In addition, the main technologies used for photon handling and conditioning, namely multilayer mirrors, adaptive optics, crystals and gratings are explained. Experiments using coherent light received during the last decades a lot of attention for the X-ray regime. Strong efforts were taken for the realization of almost fully coherent sources, e.g. the free-electron lasers, both as independent sources in the femtosecond and attosecond regimes and as seeding sources for free-electron-lasers and X-ray gas lasers. In parallel to the development of sources, optical technologies for photon handling and conditioning of such coherent and intense X-ray beams advanced. New problems were faced for the realization of optical components of beamlines demanding to manage coherent X-ray photons, e.g. the preservation of coherence and time structure of ultra short pulses.

Download or read book Industrial Applications Of Ultrafast Lasers written by Richard A Haight and published by World Scientific. This book was released on 2018-03-16 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the application of ultrafast laser science and technology in materials and processing relevant to industry today, including ultrafast laser ablation where fundamental studies have led to the development of the world's first femtosecond photomask repair tool. Semiconductor manufacturing companies worldwide use the tool to repair photomask defects, saving hundreds of millions in production costs. The most up-to-date ultrafast laser technologies are described and methods to generate high harmonics for photoelectron spectroscopy of industrially important materials are covered, with an emphasis on practical laboratory implementation. Basic device physics merged with photoemission studies from single- and polycrystalline materials are described. Extensions to new methods for extracting key device properties of metal-oxide-semiconductor structures, including band offsets, effective work functions, semiconductor band bending and defect-related charging in a number of technologically important gate oxides are detailed. Polycrystalline photovoltaic materials and heterostructures as well as organic light emitting materials are covered. This book describes both the history, and most recent applications of ultrafast laser science to industrially relevant materials, processes and devices.

Download or read book Handbook of Laser Technology and Applications written by Chunlei Guo and published by CRC Press. This book was released on 2021-06-23 with total page 733 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive handbook gives a fully updated guide to lasers and laser technologies, including the complete range of their technical applications. This third volume covers modern applications in engineering and technology, including all new and updated case studies spanning telecommunications and data storage to medicine, optical measurement, defense and security, nanomaterials processing and characterization. Key Features: • Offers a complete update of the original, bestselling work, including many brand-new chapters. • Deepens the introduction to fundamentals, from laser design and fabrication to host matrices for solid-state lasers, energy level diagrams, hosting materials, dopant energy levels, and lasers based on nonlinear effects. • Covers new laser types, including quantum cascade lasers, silicon-based lasers, titanium sapphire lasers, terahertz lasers, bismuth-doped fiber lasers, and diode-pumped alkali lasers. • Discusses the latest applications, e.g., lasers in microscopy, high-speed imaging, attosecond metrology, 3D printing, optical atomic clocks, time-resolved spectroscopy, polarization and profile measurements, pulse measurements, and laser-induced fluorescence detection. • Adds new sections on laser materials processing, laser spectroscopy, lasers in imaging, lasers in environmental sciences, and lasers in communications. This handbook is the ideal companion for scientists, engineers, and students working with lasers, including those in optics, electrical engineering, physics, chemistry, biomedicine, and other relevant areas.

Download or read book Ultrafast Nonlinear Optics written by Robert Thomson and published by Springer Science & Business Media. This book was released on 2013-03-20 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of ultrafast nonlinear optics is broad and multidisciplinary, and encompasses areas concerned with both the generation and measurement of ultrashort pulses of light, as well as those concerned with the applications of such pulses. Ultrashort pulses are extreme events – both in terms of their durations, and also the high peak powers which their short durations can facilitate. These extreme properties make them powerful experiment tools. On one hand, their ultrashort durations facilitate the probing and manipulation of matter on incredibly short timescales. On the other, their ultrashort durations can facilitate high peak powers which can drive highly nonlinear light-matter interaction processes. Ultrafast Nonlinear Optics covers a complete range of topics, both applied and fundamental in nature, within the area of ultrafast nonlinear optics. Chapters 1 to 4 are concerned with the generation and measurement of ultrashort pulses. Chapters 5 to 7 are concerned with fundamental applications of ultrashort pulses in metrology and quantum control. Chapters 8 and 9 are concerned with ultrafast nonlinear optics in optical fibres. Chapters 10 to 13 are concerned with the applications of ultrashort pulses in areas such as particle acceleration, microscopy, and micromachining. The chapters are aimed at graduate-student level and are intended to provide the student with an accessible, self-contained and comprehensive gateway into each subject.