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Wollweber T, Ayyer K. Nanoscale x-ray imaging with high spectral sensitivity using fluorescence intensity correlations. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2024; 11:024307. [PMID: 38638700 PMCID: PMC11026111 DOI: 10.1063/4.0000245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/18/2024] [Indexed: 04/20/2024]
Abstract
This paper introduces spectral incoherent diffractive imaging (SIDI) as a novel method for achieving dark-field imaging of nanostructures with heterogeneous oxidation states. With SIDI, shifts in photoemission profiles can be spatially resolved, enabling the independent imaging of the underlying emitter distributions contributing to each spectral line. In the x-ray domain, this approach offers unique insights beyond the conventional combination of diffraction and x-ray emission spectroscopy. When applied at x-ray free-electron lasers, SIDI promises to be a versatile tool for investigating a broad range of systems, offering unprecedented opportunities for detailed characterization of heterogeneous nanostructures for catalysis and energy storage, including of their ultrafast dynamics.
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Affiliation(s)
| | - Kartik Ayyer
- Author to whom correspondence should be addressed:
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2
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Peard N, Ayyer K, Chapman HN. Ab initio spatial phase retrieval via intensity triple correlations. OPTICS EXPRESS 2023; 31:25082-25092. [PMID: 37475321 DOI: 10.1364/oe.495920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/01/2023] [Indexed: 07/22/2023]
Abstract
Second-order intensity correlations from incoherent emitters can reveal the Fourier transform modulus of their spatial distribution, but retrieving the phase to enable completely general Fourier inversion to real space remains challenging. Phase retrieval via the third-order intensity correlations has relied on special emitter configurations which simplified an unaddressed sign problem in the computation. Without a complete treatment of this sign problem, the general case of retrieving the Fourier phase from a truly arbitrary configuration of emitters is not possible. In this paper, a general method for ab initio phase retrieval via the intensity triple correlations is described. Simulations demonstrate accurate phase retrieval for clusters of incoherent emitters which could be applied to imaging stars or fluorescent atoms and molecules. With this work, it is now finally tractable to perform Fourier inversion directly and reconstruct images of arbitrary arrays of independent emitters via far-field intensity correlations alone.
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3
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Trost F, Ayyer K, Prasciolu M, Fleckenstein H, Barthelmess M, Yefanov O, Dresselhaus JL, Li C, Bajt S, Carnis J, Wollweber T, Mall A, Shen Z, Zhuang Y, Richter S, Karl S, Cardoch S, Patra KK, Möller J, Zozulya A, Shayduk R, Lu W, Brauße F, Friedrich B, Boesenberg U, Petrov I, Tomin S, Guetg M, Madsen A, Timneanu N, Caleman C, Röhlsberger R, von Zanthier J, Chapman HN. Imaging via Correlation of X-Ray Fluorescence Photons. PHYSICAL REVIEW LETTERS 2023; 130:173201. [PMID: 37172237 DOI: 10.1103/physrevlett.130.173201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/01/2023] [Accepted: 03/08/2023] [Indexed: 05/14/2023]
Abstract
We demonstrate that x-ray fluorescence emission, which cannot maintain a stationary interference pattern, can be used to obtain images of structures by recording photon-photon correlations in the manner of the stellar intensity interferometry of Hanbury Brown and Twiss. This is achieved utilizing femtosecond-duration pulses of a hard x-ray free-electron laser to generate the emission in exposures comparable to the coherence time of the fluorescence. Iterative phasing of the photon correlation map generated a model-free real-space image of the structure of the emitters. Since fluorescence can dominate coherent scattering, this may enable imaging uncrystallised macromolecules.
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Affiliation(s)
- Fabian Trost
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Kartik Ayyer
- Max Planck Institute for the Structure and Dynamics of Matter, 22607, Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Mauro Prasciolu
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Holger Fleckenstein
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Miriam Barthelmess
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Oleksandr Yefanov
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - J Lukas Dresselhaus
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Chufeng Li
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Saša Bajt
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Jerome Carnis
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
| | - Tamme Wollweber
- Max Planck Institute for the Structure and Dynamics of Matter, 22607, Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Abhishek Mall
- Max Planck Institute for the Structure and Dynamics of Matter, 22607, Hamburg, Germany
| | - Zhou Shen
- Max Planck Institute for the Structure and Dynamics of Matter, 22607, Hamburg, Germany
| | - Yulong Zhuang
- Max Planck Institute for the Structure and Dynamics of Matter, 22607, Hamburg, Germany
| | - Stefan Richter
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstrasse 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052, Erlangen, Germany
| | - Sebastian Karl
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstrasse 1, 91058 Erlangen, Germany
| | - Sebastian Cardoch
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-75120, Sweden
| | - Kajwal Kumar Patra
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-75120, Sweden
| | - Johannes Möller
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Alexey Zozulya
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Roman Shayduk
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Wei Lu
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Felix Brauße
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Bertram Friedrich
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Ulrike Boesenberg
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Ilia Petrov
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Sergey Tomin
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Marc Guetg
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Anders Madsen
- European X-Ray Free-Electron Laser Facility, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Nicusor Timneanu
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-75120, Sweden
| | - Carl Caleman
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-75120, Sweden
| | - Ralf Röhlsberger
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
- Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 62491 Jena, Germany
- Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany
| | - Joachim von Zanthier
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstrasse 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052, Erlangen, Germany
| | - Henry N Chapman
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala SE-75120, Sweden
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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Yoneda N, Quan X, Matoba O. Single-shot generalized Hanbury Brown-Twiss experiments using a polarization camera for target intensity reconstruction in scattering media. OPTICS LETTERS 2023; 48:632-635. [PMID: 36723550 DOI: 10.1364/ol.479475] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/06/2023] [Indexed: 06/18/2023]
Abstract
To see through a random light field in real-time, single-shot generalized Hanbury Brown-Twiss experiments using a polarization camera are proposed. The target intensity distribution is obtained from a complex coherence function which is calculated from auto-correlation and cross correlation functions of phase-shifted speckle intensity distributions. The phase-shifted speckle intensity distributions are simultaneously obtained through a strategy of parallel phase-shifting digital holography. Experimental results show that the proposed method can image a moving object in a random light field using a measured complex coherence function through the van Cittert-Zernike theorem.
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Trost F, Ayyer K, Oberthuer D, Yefanov O, Bajt S, Caleman C, Weimer A, Feld A, Weller H, Boutet S, Koglin J, Timneanu N, von Zanthier J, Röhlsberger R, Chapman HN. Speckle contrast of interfering fluorescence X-rays. JOURNAL OF SYNCHROTRON RADIATION 2023; 30:11-23. [PMID: 36601922 PMCID: PMC9814059 DOI: 10.1107/s1600577522009997] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 10/12/2022] [Indexed: 05/27/2023]
Abstract
With the development of X-ray free-electron lasers (XFELs), producing pulses of femtosecond durations comparable with the coherence times of X-ray fluorescence, it has become possible to observe intensity-intensity correlations due to the interference of emission from independent atoms. This has been used to compare durations of X-ray pulses and to measure the size of a focusedX-ray beam, for example. Here it is shown that it is also possible to observe the interference of fluorescence photons through the measurement of the speckle contrast of angle-resolved fluorescence patterns. Speckle contrast is often used as a measure of the degree of coherence of the incident beam or the fluctuations of the illuminated sample as determined from X-ray diffraction patterns formed by elastic scattering, rather than from fluorescence patterns as addressed here. Commonly used approaches to estimate speckle contrast were found to suffer when applied to XFEL-generated fluorescence patterns due to low photon counts and a significant variation of the excitation pulse energy from shot to shot. A new method to reliably estimate speckle contrast under such conditions, using a weighting scheme, is introduced. The method is demonstrated by comparing the speckle contrast of fluorescence observed with pulses of 3 fs to 15 fs duration.
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Affiliation(s)
- Fabian Trost
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
| | - Kartik Ayyer
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
| | - Dominik Oberthuer
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Oleksandr Yefanov
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Saša Bajt
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
| | - Carl Caleman
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - Agnes Weimer
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Institute of Physical Chemistry, Universität Hamburg, Grindelallee 117, D-20146 Hamburg, Germany
| | - Artur Feld
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Institute of Physical Chemistry, Universität Hamburg, Grindelallee 117, D-20146 Hamburg, Germany
| | - Horst Weller
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Institute of Physical Chemistry, Universität Hamburg, Grindelallee 117, D-20146 Hamburg, Germany
- Department of Chemistry, Fraunhofer-CAN, Grindelallee 117, D-20146 Hamburg, Germany
| | - Sébastien Boutet
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jason Koglin
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Nicusor Timneanu
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
| | - Joachim von Zanthier
- AG Quantum Optics and Quantum Information, University of Erlangen-Nürnberg, Staudtstrasse 1, D-91058 Erlangen, Germany
| | - Ralf Röhlsberger
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, Hamburg, Germany
| | - Henry N. Chapman
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany
- Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, Hamburg, Germany
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6
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Cardoch S, Trost F, Scott HA, Chapman HN, Caleman C, Timneanu N. Decreasing ultrafast x-ray pulse durations with saturable absorption and resonant transitions. Phys Rev E 2023; 107:015205. [PMID: 36797944 DOI: 10.1103/physreve.107.015205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 12/09/2022] [Indexed: 01/19/2023]
Abstract
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 reduction in the temporal duration of transmitted x-ray laser pulses, but a detailed account of changes in opacity and emergence of resonances is still missing. In this computational work, we employ nonlocal thermodynamic equilibrium plasma simulations to study the interaction of femtosecond x rays and copper. Following the onset of frustrated absorption, we find that a K-M resonant transition occurring at highly charged states turns copper opaque again. The changes in absorption generate a transient transparent window responsible for the shortened transmission signal. We also propose using fluorescence induced by the incident beam as an alternative source to achieve shorter x-ray pulses. Intense femtosecond x rays are valuable to probe the structure and dynamics of biological samples or to reach extreme states of matter. Shortened pulses could be relevant for emerging imaging techniques.
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Affiliation(s)
- Sebastian Cardoch
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
| | - Fabian Trost
- Center for Free-Electron Laser Science CFEL, Deutsches-Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Howard A Scott
- Lawrence Livermore National Laboratory, L-18, P.O. Box 808, Livermore, California 94550, USA
| | - Henry N Chapman
- Center for Free-Electron Laser Science CFEL, Deutsches-Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.,The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.,Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Carl Caleman
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden.,Center for Free-Electron Laser Science CFEL, Deutsches-Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Nicusor Timneanu
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
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7
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Numerical Simulation of Heat Load for Multilayer Laue Lens under Exposure to XFEL Pulse Trains. PHOTONICS 2022. [DOI: 10.3390/photonics9050362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Multilayer Laue lenses (MLLs) made from WC and SiC were previously used to focus megahertz X-ray pulse trains of the European XFEL free-electron laser, but suffered damage with trains of 30 pulses or longer at an incident fluence of about 0.13 J/cm2 per pulse. Here, we present numerical simulations of the heating of MLLs of various designs, geometry and material properties, that are exposed to such pulse trains. We find that it should be possible to focus the full beam of about 10 J/cm2 fluence of XFEL using materials of a low atomic number. To achieve high diffraction efficiency, lenses made from such materials should be considerably thicker than those used in the experiments. In addition to the lower absorption, this leads to the deposition of energy over a larger volume of the multilayer structure and hence to a lower dose, a lower temperature increase, and an improved dissipation of heat.
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8
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Keramati S, Brunner W, Gay TJ, Batelaan H. Non-Poissonian Ultrashort Nanoscale Electron Pulses. PHYSICAL REVIEW LETTERS 2021; 127:180602. [PMID: 34767409 DOI: 10.1103/physrevlett.127.180602] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/09/2021] [Accepted: 09/28/2021] [Indexed: 05/12/2023]
Abstract
The statistical character of electron beams used in current technologies, as described by a stream of particles, is random in nature. Using coincidence measurements of femtosecond pulsed electron pairs, we report the observation of sub-Poissonian electron statistics that are nonrandom due to two-electron Coulomb interactions, and that exhibit an antibunching signal of 1 part in 4. This advancement is a fundamental step toward observing a strongly quantum degenerate electron beam needed for many applications, and in particular electron correlation spectroscopy.
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Affiliation(s)
- Sam Keramati
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Will Brunner
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - T J Gay
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Herman Batelaan
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
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9
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Lohse LM, Vassholz M, Salditt T. On incoherent diffractive imaging. Acta Crystallogr A Found Adv 2021; 77:480-496. [PMID: 34473101 PMCID: PMC8477639 DOI: 10.1107/s2053273321007300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/14/2021] [Indexed: 11/10/2022] Open
Abstract
Incoherent diffractive imaging (IDI) promises structural analysis with atomic resolution based on intensity interferometry of pulsed X-ray fluorescence emission. However, its experimental realization is still pending and a comprehensive theory of contrast formation has not been established to date. Explicit expressions are derived for the equal-pulse two-point intensity correlations, as the principal measured quantity of IDI, with full control of the prefactors, based on a simple model of stochastic fluorescence emission. The model considers the photon detection statistics, the finite temporal coherence of the individual emissions, as well as the geometry of the scattering volume. The implications are interpreted in view of the most relevant quantities, including the fluorescence lifetime, the excitation pulse, as well as the extent of the scattering volume and pixel size. Importantly, the spatiotemporal overlap between any two emissions in the sample can be identified as a crucial factor limiting the contrast and its dependency on the sample size can be derived. The paper gives rigorous estimates for the optimum sample size, the maximum photon yield and the expected signal-to-noise ratio under optimal conditions. Based on these estimates, the feasibility of IDI experiments for plausible experimental parameters is discussed. It is shown in particular that the mean number of photons per detector pixel which can be achieved with X-ray fluorescence is severely limited and as a consequence imposes restrictive constraints on possible applications.
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Affiliation(s)
- Leon M Lohse
- Institut für Röntgenphysik, Universität Göttingen, Germany
| | - Malte Vassholz
- Institut für Röntgenphysik, Universität Göttingen, Germany
| | - Tim Salditt
- Institut für Röntgenphysik, Universität Göttingen, Germany
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10
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Ho PJ, Knight C, Young L. Fluorescence intensity correlation imaging with high spatial resolution and elemental contrast using intense x-ray pulses. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2021; 8:044101. [PMID: 34368392 PMCID: PMC8324305 DOI: 10.1063/4.0000105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 07/07/2021] [Indexed: 05/27/2023]
Abstract
We theoretically investigate the fluorescence intensity correlation (FIC) of Ar clusters and Mo-doped iron oxide nanoparticles subjected to intense, femtosecond, and sub-femtosecond x-ray free-electron laser pulses for high-resolution and elemental contrast imaging. We present the FIC of K α and K α h emission in Ar clusters and discuss the impact of sample damage on retrieving high-resolution structural information and compare the obtained structural information with those from the coherent diffractive imaging (CDI) approach. We found that, while sub-femtosecond pulses will substantially benefit the CDI approach, few-femtosecond pulses may be sufficient for achieving high-resolution information with the FIC. Furthermore, we show that the fluorescence intensity correlation computed from the fluorescence of the Mo atoms in Mo-doped iron oxide nanoparticles can be used to image dopant distributions in the nonresonant regime.
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Affiliation(s)
- Phay J. Ho
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Christopher Knight
- Computational Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
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11
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Richter S, Wolf S, von Zanthier J, Schmidt-Kaler F. Imaging Trapped Ion Structures via Fluorescence Cross-Correlation Detection. PHYSICAL REVIEW LETTERS 2021; 126:173602. [PMID: 33988402 DOI: 10.1103/physrevlett.126.173602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 03/30/2021] [Indexed: 06/12/2023]
Abstract
Cross-correlation signals are recorded from fluorescence photons scattered in free space off a trapped ion structure. The analysis of the signal allows for unambiguously revealing the spatial frequency, thus the distance, as well as the spatial alignment of the ions. For the case of two ions we obtain from the cross-correlations a spatial frequency f_{spatial}=1490±2_{stat}±8_{syst} rad^{-1}, where the statistical uncertainty improves with the integrated number of correlation events as N^{-0.51±0.06}. We independently determine the spatial frequency to be 1494±11 rad^{-1}, proving excellent agreement. Expanding our method to the case of three ions, we demonstrate its functionality for two-dimensional arrays of emitters of indistinguishable photons, serving as a model system to yield structural information where direct imaging techniques fail.
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Affiliation(s)
- Stefan Richter
- Institut für Optik, Information und Photonik, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstraße 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Straße 6, 91052 Erlangen, Germany
| | - Sebastian Wolf
- QUANTUM, Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Joachim von Zanthier
- Institut für Optik, Information und Photonik, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstraße 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Straße 6, 91052 Erlangen, Germany
| | - Ferdinand Schmidt-Kaler
- QUANTUM, Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
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12
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13
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Wolf S, Richter S, von Zanthier J, Schmidt-Kaler F. Light of Two Atoms in Free Space: Bunching or Antibunching? PHYSICAL REVIEW LETTERS 2020; 124:063603. [PMID: 32109104 DOI: 10.1103/physrevlett.124.063603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
Photon statistics divides light sources into three different categories, characterized by bunched, antibunched, or uncorrelated photon arrival times. Single atoms, ions, molecules, or solid state emitters display antibunching of photons, while classical thermal sources exhibit photon bunching. Here we demonstrate a light source in free space, where the photon statistics depends on the direction of observation, undergoing a continuous crossover between photon bunching and antibunching. We employ two trapped ions, observe their fluorescence under continuous laser light excitation, and record spatially resolved the autocorrelation function g^{(2)}(τ) with a movable Hanbury Brown and Twiss detector. Varying the detector position we find a minimum value for antibunching, g^{(2)}(0)=0.60(5) and a maximum of g^{(2)}(0)=1.46(8) for bunching, demonstrating that this source radiates fundamentally different types of light alike. The observed variation of the autocorrelation function is understood in the Dicke model from which the observed maximum and minimum values can be modeled, taking independently measured experimental parameters into account.
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Affiliation(s)
- Sebastian Wolf
- QUANTUM, Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Stefan Richter
- Institut für Optik, Information und Photonik, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstraße 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Straße 6, 91052 Erlangen, Germany
| | - Joachim von Zanthier
- Institut für Optik, Information und Photonik, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstraße 1, 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Straße 6, 91052 Erlangen, Germany
| | - Ferdinand Schmidt-Kaler
- QUANTUM, Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany
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14
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Inoue I, Tamasaku K, Osaka T, Inubushi Y, Yabashi M. Determination of X-ray pulse duration via intensity correlation measurements of X-ray fluorescence. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:2050-2054. [PMID: 31721750 DOI: 10.1107/s1600577519011202] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/11/2019] [Indexed: 06/10/2023]
Abstract
A simple method using X-ray fluorescence is proposed to diagnose the duration of an X-ray free-electron laser (XFEL) pulse. This work shows that the degree of intensity correlation of the X-ray fluorescence generated by irradiating an XFEL pulse on metal foil reflects the magnitude relation between the XFEL duration and the coherence time of the fluorescence. Through intensity correlation measurements of copper Kα fluorescence, the duration of 12 keV XFEL pulses from SACLA was evaluated to be ∼10 fs.
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Affiliation(s)
- Ichiro Inoue
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Kenji Tamasaku
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Taito Osaka
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Yuichi Inubushi
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Makina Yabashi
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
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15
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Abstract
X-ray free-electron lasers provide femtosecond-duration pulses of hard X-rays with a peak brightness approximately one billion times greater than is available at synchrotron radiation facilities. One motivation for the development of such X-ray sources was the proposal to obtain structures of macromolecules, macromolecular complexes, and virus particles, without the need for crystallization, through diffraction measurements of single noncrystalline objects. Initial explorations of this idea and of outrunning radiation damage with femtosecond pulses led to the development of serial crystallography and the ability to obtain high-resolution structures of small crystals without the need for cryogenic cooling. This technique allows the understanding of conformational dynamics and enzymatics and the resolution of intermediate states in reactions over timescales of 100 fs to minutes. The promise of more photons per atom recorded in a diffraction pattern than electrons per atom contributing to an electron micrograph may enable diffraction measurements of single molecules, although challenges remain.
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Affiliation(s)
- Henry N. Chapman
- Center for Free-Electron Laser Science, DESY, 22607 Hamburg, Germany
- Department of Physics, University of Hamburg, 22761 Hamburg, Germany
- Centre for Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany
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16
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Hantke MF, Bielecki J, Kulyk O, Westphal D, Larsson DSD, Svenda M, Reddy HKN, Kirian RA, Andreasson J, Hajdu J, Maia FRNC. Rayleigh-scattering microscopy for tracking and sizing nanoparticles in focused aerosol beams. IUCRJ 2018; 5:673-680. [PMID: 30443352 PMCID: PMC6211534 DOI: 10.1107/s2052252518010837] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/26/2018] [Indexed: 05/25/2023]
Abstract
Ultra-bright femtosecond X-ray pulses generated by X-ray free-electron lasers (XFELs) can be used to image high-resolution structures without the need for crystallization. For this approach, aerosol injection has been a successful method to deliver 70-2000 nm particles into the XFEL beam efficiently and at low noise. Improving the technique of aerosol sample delivery and extending it to single proteins necessitates quantitative aerosol diagnostics. Here a lab-based technique is introduced for Rayleigh-scattering microscopy allowing us to track and size aerosolized particles down to 40 nm in diameter as they exit the injector. This technique was used to characterize the 'Uppsala injector', which is a pioneering and frequently used aerosol sample injector for XFEL single-particle imaging. The particle-beam focus, particle velocities, particle density and injection yield were measured at different operating conditions. It is also shown how high particle densities and good injection yields can be reached for large particles (100-500 nm). It is found that with decreasing particle size, particle densities and injection yields deteriorate, indicating the need for different injection strategies to extend XFEL imaging to smaller targets, such as single proteins. This work demonstrates the power of Rayleigh-scattering microscopy for studying focused aerosol beams quantitatively. It lays the foundation for lab-based injector development and online injection diagnostics for XFEL research. In the future, the technique may also find application in other fields that employ focused aerosol beams, such as mass spectrometry, particle deposition, fuel injection and three-dimensional printing techniques.
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Affiliation(s)
- Max F. Hantke
- Chemistry Research Laboratory, Department of Chemistry, Oxford University, 12 Mansfield Rd, Oxford OX1 3TA, UK
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
| | - Johan Bielecki
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
- European XFEL GmbH, Holzkoppel 4, Schenefeld 22869, Germany
| | - Olena Kulyk
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, Na Slovance 2, Prague CZ-18221, Czech Republic
| | - Daniel Westphal
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
| | - Daniel S. D. Larsson
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
| | - Martin Svenda
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
| | - Hemanth K. N. Reddy
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
| | - Richard A. Kirian
- Department of Physics, Arizona State University, 550 E. Tyler Drive, Tempe, AZ 85287, USA
| | - Jakob Andreasson
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, Na Slovance 2, Prague CZ-18221, Czech Republic
- Condensed Matter Physics, Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Janos Hajdu
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, Na Slovance 2, Prague CZ-18221, Czech Republic
| | - Filipe R. N. C. Maia
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3 (Box 596), Uppsala SE-75124, Sweden
- NERSC, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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17
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Schneider R, Biernoth C, Hölzl J, Pscherer A, von Zanthier J. Simulating the photon stream of a real thermal light source. APPLIED OPTICS 2018; 57:7076-7080. [PMID: 30129602 DOI: 10.1364/ao.57.007076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 07/21/2018] [Indexed: 06/08/2023]
Abstract
We present a computer algorithm capable of simulating the photon stream and the corresponding temporal photon statistics of thermal light sources. The algorithm implements realistic experimental conditions, incorporating the relevant parameters of the source as well as of the detection process. The code is verified by comparing the temporal photon autocorrelation function computed from the simulations to the one measured with a real thermal light source. In view of the renewed interest for intensity interferometry in astronomy and the life sciences, such simulations become increasingly relevant.
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18
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Wang W, Chen H, Yuan Y, Han Q, Wang G, Zheng H, Liu J, Xu Z. Ptychographical intensity interferometry imaging with incoherent light. OPTICS EXPRESS 2018; 26:20396-20408. [PMID: 30119350 DOI: 10.1364/oe.26.020396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
Intensity interferometry (II), the landmark of the second-order correlation, enables very long baseline observations at optical wavelengths, providing imaging with microarcsecond resolution. However, the unreliability of traditional phase retrieval algorithms required to reconstruct images in II has hindered its development. We here develop a method that circumvents this challenge, which enables II to reliably image complex shaped objects. Instead of measuring the whole object, we measure it part by part with a probe moving in a ptychographic way: adjacent parts overlap with each other. A relevant algorithm is developed to reliably and rapidly recover the object in a few iterations. Moreover, we propose an approach to remove the requirement for a precise knowledge of the probe, providing an error-tolerance of more than 50% for the location of the probe in our experiments. Furthermore, we extend II to short distance scenarios, providing a lensless imaging method with incoherent light and paving a way towards applications in X-ray imaging.
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19
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Xavier PL, Chandrasekaran AR. DNA-based construction at the nanoscale: emerging trends and applications. NANOTECHNOLOGY 2018; 29:062001. [PMID: 29232197 DOI: 10.1088/1361-6528/aaa120] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The field of structural DNA nanotechnology has evolved remarkably-from the creation of artificial immobile junctions to the recent DNA-protein hybrid nanoscale shapes-in a span of about 35 years. It is now possible to create complex DNA-based nanoscale shapes and large hierarchical assemblies with greater stability and predictability, thanks to the development of computational tools and advances in experimental techniques. Although it started with the original goal of DNA-assisted structure determination of difficult-to-crystallize molecules, DNA nanotechnology has found its applications in a myriad of fields. In this review, we cover some of the basic and emerging assembly principles: hybridization, base stacking/shape complementarity, and protein-mediated formation of nanoscale structures. We also review various applications of DNA nanostructures, with special emphasis on some of the biophysical applications that have been reported in recent years. In the outlook, we discuss further improvements in the assembly of such structures, and explore possible future applications involving super-resolved fluorescence, single-particle cryo-electron (cryo-EM) and x-ray free electron laser (XFEL) nanoscopic imaging techniques, and in creating new synergistic designer materials.
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Affiliation(s)
- P Lourdu Xavier
- Center for Free Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY) and Department of Physics, University of Hamburg, D-22607 Hamburg, Germany. Max-Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, D-22761 Hamburg, Germany
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20
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Gorobtsov OY, Mukharamova N, Lazarev S, Chollet M, Zhu D, Feng Y, Kurta RP, Meijer JM, Williams G, Sikorski M, Song S, Dzhigaev D, Serkez S, Singer A, Petukhov AV, Vartanyants IA. Diffraction based Hanbury Brown and Twiss interferometry at a hard x-ray free-electron laser. Sci Rep 2018; 8:2219. [PMID: 29396400 PMCID: PMC5797123 DOI: 10.1038/s41598-018-19793-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 01/05/2018] [Indexed: 11/30/2022] Open
Abstract
X-ray free-electron lasers (XFELs) provide extremely bright and highly spatially coherent x-ray radiation with femtosecond pulse duration. Currently, they are widely used in biology and material science. Knowledge of the XFEL statistical properties during an experiment may be vitally important for the accurate interpretation of the results. Here, for the first time, we demonstrate Hanbury Brown and Twiss (HBT) interferometry performed in diffraction mode at an XFEL source. It allowed us to determine the XFEL statistical properties directly from the Bragg peaks originating from colloidal crystals. This approach is different from the traditional one when HBT interferometry is performed in the direct beam without a sample. Our analysis has demonstrated nearly full (80%) global spatial coherence of the XFEL pulses and an average pulse duration on the order of ten femtoseconds for the monochromatized beam, which is significantly shorter than expected from the electron bunch measurements.
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Affiliation(s)
- O Yu Gorobtsov
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany
| | - N Mukharamova
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany
| | - S Lazarev
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany
- National Research Tomsk Polytechnic University (TPU), Lenin Avenue 30, 634050, Tomsk, Russia
| | - M Chollet
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
| | - D Zhu
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
| | - Y Feng
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
| | - R P Kurta
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany
- European XFEL GmbH, Holzkoppel 4, D-22869, Schenefeld, Germany
| | - J-M Meijer
- Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterial Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, Netherlands
- Department of Physics, University of Konstanz, D-78457, Konstanz, Germany
| | - G Williams
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
- NSLS-II, Brookhaven National Laboratory, 53 Bell Avenue, Upton, NY, 11973-5000, USA
| | - M Sikorski
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
- European XFEL GmbH, Holzkoppel 4, D-22869, Schenefeld, Germany
| | - S Song
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, 94025, CA, USA
| | - D Dzhigaev
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany
| | - S Serkez
- European XFEL GmbH, Holzkoppel 4, D-22869, Schenefeld, Germany
| | - A Singer
- University of California San Diego, 9500 Gilman Dr., La Jolla, California, 92093, USA
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14850, USA
| | - A V Petukhov
- Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterial Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, Netherlands
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, Netherlands
| | - I A Vartanyants
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, D-22607, Hamburg, Germany.
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, 115409, Moscow, Russia.
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