High current table-top setup for femtosecond gas electron diffraction
Abstract
Here, we have constructed an experimental setup for gas phase electron diffraction with femtosecond resolution and a high average beam current. While gas electron diffraction has been successful at determining molecular structures, it has been a challenge to reach femtosecond resolution while maintaining sufficient beam current to retrieve structures with high spatial resolution. The main challenges are the Coulomb force that leads to broadening of the electron pulses and the temporal blurring that results from the velocity mismatch between the laser and electron pulses as they traverse the sample. We also present here a device that uses pulse compression to overcome the Coulomb broadening and deliver femtosecond electron pulses on a gas target. The velocity mismatch can be compensated using laser pulses with a tilted intensity front to excite the sample. The temporal resolution of the setup was determined with a streak camera to be better than 400 fs for pulses with up to half a million electrons and a kinetic energy of 90 keV. Finally, the high charge per pulse, combined with a repetition rate of 5 kHz, results in an average beam current that is between one and two orders of magnitude higher than previously demonstrated.
- Authors:
-
- Univ. of Nebraska, Lincoln, NE (United States). Dept. of Physics and Astronomy
- Publication Date:
- Research Org.:
- Univ. of Nebraska, Lincoln, NE (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1374554
- Grant/Contract Number:
- SC0014170
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Structural Dynamics
- Additional Journal Information:
- Journal Volume: 4; Journal Issue: 4; Journal ID: ISSN 2329-7778
- Publisher:
- American Crystallographic Association/AIP
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 43 PARTICLE ACCELERATORS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Citation Formats
Zandi, Omid, Wilkin, Kyle J., Xiong, Yanwei, and Centurion, Martin. High current table-top setup for femtosecond gas electron diffraction. United States: N. p., 2017.
Web. doi:10.1063/1.4983225.
Zandi, Omid, Wilkin, Kyle J., Xiong, Yanwei, & Centurion, Martin. High current table-top setup for femtosecond gas electron diffraction. United States. https://doi.org/10.1063/1.4983225
Zandi, Omid, Wilkin, Kyle J., Xiong, Yanwei, and Centurion, Martin. Mon .
"High current table-top setup for femtosecond gas electron diffraction". United States. https://doi.org/10.1063/1.4983225. https://www.osti.gov/servlets/purl/1374554.
@article{osti_1374554,
title = {High current table-top setup for femtosecond gas electron diffraction},
author = {Zandi, Omid and Wilkin, Kyle J. and Xiong, Yanwei and Centurion, Martin},
abstractNote = {Here, we have constructed an experimental setup for gas phase electron diffraction with femtosecond resolution and a high average beam current. While gas electron diffraction has been successful at determining molecular structures, it has been a challenge to reach femtosecond resolution while maintaining sufficient beam current to retrieve structures with high spatial resolution. The main challenges are the Coulomb force that leads to broadening of the electron pulses and the temporal blurring that results from the velocity mismatch between the laser and electron pulses as they traverse the sample. We also present here a device that uses pulse compression to overcome the Coulomb broadening and deliver femtosecond electron pulses on a gas target. The velocity mismatch can be compensated using laser pulses with a tilted intensity front to excite the sample. The temporal resolution of the setup was determined with a streak camera to be better than 400 fs for pulses with up to half a million electrons and a kinetic energy of 90 keV. Finally, the high charge per pulse, combined with a repetition rate of 5 kHz, results in an average beam current that is between one and two orders of magnitude higher than previously demonstrated.},
doi = {10.1063/1.4983225},
journal = {Structural Dynamics},
number = 4,
volume = 4,
place = {United States},
year = {Mon May 08 00:00:00 EDT 2017},
month = {Mon May 08 00:00:00 EDT 2017}
}
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Dark Structures in Molecular Radiationless Transitions Determined by Ultrafast Diffraction
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New electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range
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Works referencing / citing this record:
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- Otto, M. R.; René de Cotret, L. P.; Stern, M. J.
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Solving the jitter problem in microwave compressed ultrafast electron diffraction instruments: Robust sub-50 fs cavity-laser phase stabilization
journal, September 2017
- Otto, M. R.; René de Cotret, L. P.; Stern, M. J.
- Structural Dynamics, Vol. 4, Issue 5