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Makita M, Vartiainen I, Mohacsi I, Caleman C, Diaz A, Jönsson HO, Juranić P, Medvedev N, Meents A, Mozzanica A, Opara NL, Padeste C, Panneels V, Saxena V, Sikorski M, Song S, Vera L, Willmott PR, Beaud P, Milne CJ, Ziaja-Motyka B, David C. Femtosecond phase-transition in hard x-ray excited bismuth. Sci Rep 2019; 9:602. [PMID: 30679456 PMCID: PMC6345934 DOI: 10.1038/s41598-018-36216-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 11/14/2018] [Indexed: 11/26/2022] Open
Abstract
The evolution of bismuth crystal structure upon excitation of its A1g phonon has been intensely studied with short pulse optical lasers. Here we present the first-time observation of a hard x-ray induced ultrafast phase transition in a bismuth single crystal at high intensities (~1014 W/cm2). The lattice evolution was followed using a recently demonstrated x-ray single-shot probing setup. The time evolution of the (111) Bragg peak intensity showed strong dependence on the excitation fluence. After exposure to a sufficiently intense x-ray pulse, the peak intensity dropped to zero within 300 fs, i.e. faster than one oscillation period of the A1g mode at room temperature. Our analysis indicates a nonthermal origin of a lattice disordering process, and excludes interpretations based on electron-ion equilibration process, or on thermodynamic heating process leading to plasma formation.
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Affiliation(s)
- M Makita
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.
| | - I Vartiainen
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - I Mohacsi
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.,Synchrotron SOLEIL, L'Orme des Merisiers, 91190, Saint-Aubin, France
| | - C Caleman
- CFEL, Deutsches Elektronen-Synchrotron DESY, 22607, Hamburg, Germany.,Department of Physics and Astronomy, Uppsala University, SE-751 24, Uppsala, Sweden
| | - A Diaz
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - H O Jönsson
- Department of Physics and Astronomy, Uppsala University, SE-751 24, Uppsala, Sweden.,Department of Applied physics, KTH Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - P Juranić
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - N Medvedev
- Institute of Physics, Czech Academy of Sciences, 182 21, Prague 8, Czech Republic.,Institute of Plasma Physics, Czech Academy of Sciences, 182 00, Prague 8, Czech Republic
| | - A Meents
- CFEL, Deutsches Elektronen-Synchrotron DESY, 22607, Hamburg, Germany
| | - A Mozzanica
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - N L Opara
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland.,C-CINA Biozentrum, University of Basel, CH-4058, Basel, Switzerland
| | - C Padeste
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - V Panneels
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - V Saxena
- CFEL, Deutsches Elektronen-Synchrotron DESY, 22607, Hamburg, Germany.,Institute for Plasma Research, Bhat, Gandhinagar, 382428, India
| | - M Sikorski
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, 94025, USA
| | - S Song
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California, 94025, USA
| | - L Vera
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - P R Willmott
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - P Beaud
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - C J Milne
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - B Ziaja-Motyka
- CFEL, Deutsches Elektronen-Synchrotron DESY, 22607, Hamburg, Germany.,Institute of Nuclear Physics, Polish Academy of Sciences, 31-342, Krakow, Poland
| | - C David
- Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
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Single-shot real-time sub-nanosecond electron imaging aided by compressed sensing: Analytical modeling and simulation. Micron 2018; 117:47-54. [PMID: 30472498 DOI: 10.1016/j.micron.2018.11.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 11/20/2022]
Abstract
Bringing ultrafast (nanosecond and below) temporal resolution to transmission electron microscopy (TEM) has historically been challenging. Despite significant recent progress in this direction, it remains difficult to achieve sub-nanosecond temporal resolution with a single electron pulse, in real-time (i.e., duration in which the event occurs) imaging. To address this limitation, here, we propose a methodology that combines laser-assisted TEM with computational imaging methodologies based on compressed sensing (CS). In this technique, a two-dimensional (2D) transient event [i.e. (x,y) frames that vary in time] is recorded through a CS paradigm, which consists of spatial encoding, temporal shearing via streaking, and spatiotemporal integration of an electron pulse. The 2D image generated on a camera is used to reconstruct the datacube of the ultrafast event, with two spatial and one temporal dimensions, via a CS-based image reconstruction algorithm. Using numerical simulation, we find that the reconstructed results are in good agreement with the ground truth, which demonstrates the applicability of CS-based computational imaging methodologies to laser-assisted TEM. Our proposed method, complementing the existing ultrafast stroboscopic and nanosecond single-shot techniques, opens up the possibility for single-shot, real-time, spatiotemporal imaging of irreversible structural phenomena with sub-nanosecond temporal resolution.
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