Emission direction of fast electrons in laser-solid interactions at intensities from the nonrelativistic to the relativistic

The emission of high-energy protons in laser–solid interactions and the theories that have been used to explain it are briefly reviewed. To these theories we add a further possibility: the acceleration of protons inside the target by the electric field generated by fast electrons. This is considered using a simple one-dimensional model. It is found that for relativistic laser intensities and sufficiently long pulse durations, the proton energy gain is typically several times the fast electron temperature. The results are very similar to those obtained for proton acceleration by electron expansion into vacuum.

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Two-plasmon-decay induced fast electrons in intense femtosecond laser–solid interactions

Physics of Plasmas ◽

10.1063/5.0012590 ◽

2020 ◽

Vol 27 (8) ◽

pp. 083105

Author(s):

Prashant Kumar Singh ◽

Amitava Adak ◽

Amit D. Lad ◽

Gourab Chatterjee ◽

G. Ravindra Kumar

Keyword(s):

Femtosecond Laser ◽

Fast Electrons ◽

Laser Solid Interactions

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Design of Sensitive Photographic Materials for the High-Voltage Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114402 ◽

1975 ◽

Vol 33 ◽

pp. 156-157

Author(s):

Murray Vernon King ◽

Donald F. Parsons

Keyword(s):

Electron Microscope ◽

Radiation Damage ◽

High Voltage ◽

Radiation Sensitivity ◽

Fast Electrons ◽

Voltage Electron ◽

High Voltage Electron Microscope ◽

High Voltage Electron ◽

Biological Studies ◽

Low Sensitivity

Effective application of the high-voltage electron microscope to a wide variety of biological studies has been restricted by the radiation sensitivity of biological systems. The problem of radiation damage has been recognized as a serious factor influencing the amount of information attainable from biological specimens in electron microscopy at conventional voltages around 100 kV. The problem proves to be even more severe at higher voltages around 1 MV. In this range, the problem is the relatively low sensitivity of the existing recording media, which entails inordinately long exposures that give rise to severe radiation damage. This low sensitivity arises from the small linear energy transfer for fast electrons. Few developable grains are created in the emulsion per electron, while most of the energy of the electrons is wasted in the film base.

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High-angle electron scattering from amorphous silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137185 ◽

1995 ◽

Vol 53 ◽

pp. 162-163

Author(s):

M. Libera ◽

J.A. Ott ◽

K. Siangchaew ◽

L. Tsung

Keyword(s):

Electron Scattering ◽

Amorphous Material ◽

Structural Defects ◽

Constant Thickness ◽

High Angle ◽

Fast Electrons ◽

Angle Scattering ◽

Stem Image ◽

Amorphous Si ◽

Thermal Vibrations

Channeling occurs when fast electrons follow atomic strings in a crystal where there is a minimum in the potential energy (1). Channeling has a strong effect on high-angle scattering. Deviations in atomic position along a channel due to structural defects or thermal vibrations increase the probability of scattering (2-5). Since there are no extended channels in an amorphous material the question arises: for a given material with constant thickness, will the high-angle scattering be higher from a crystal or a glass?Figure la shows a HAADF STEM image collected using a Philips CM20 FEG TEM/STEM with inner and outer collection angles of 35mrad and lOOmrad. The specimen (6) was a cross section of singlecrystal Si containing: amorphous Si (region A), defective Si containing many stacking faults (B), two coherent Ge layers (CI; C2), and a contamination layer (D). CBED patterns (fig. lb), PEELS spectra, and HAADF signals (fig. lc) were collected at 106K and 300K along the indicated line.

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Laser-solid interactions

AccessScience ◽

10.1036/1097-8542.372350 ◽

2015 ◽

Keyword(s):

Laser Solid Interactions

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lonization and quenching of excited atoms with the production of fast electrons

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0163.199303c.0055 ◽

1993 ◽

Vol 163 (3) ◽

pp. 55-77 ◽

Cited By ~ 20

Author(s):

N.B. Kolokolov ◽

A.B. Blagoev

Keyword(s):

Fast Electrons ◽

Excited Atoms

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Suppression of vortex lattice melting in YBCO via irradiation with fast electrons

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-019-00978-x ◽

2019 ◽

Vol 30 (7) ◽

pp. 6688-6692

Author(s):

V. I. Beletskiy ◽

G. Ya. Khadzhai ◽

R. V. Vovk ◽

N. R. Vovk ◽

A. V. Samoylov ◽

...

Keyword(s):

Vortex Lattice ◽

Fast Electrons ◽

Vortex Lattice Melting

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Downscaled Finite Element Modeling of Metal Targets for Surface Roughness Level under Pulsed Laser Irradiation

Applied Sciences ◽

10.3390/app11031253 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1253

Author(s):

Evaggelos Kaselouris ◽

Kyriaki Kosma ◽

Yannis Orphanos ◽

Alexandros Skoulakis ◽

Ioannis Fitilis ◽

...

Keyword(s):

Surface Roughness ◽

Finite Element ◽

Surface Acoustic Waves ◽

Pulsed Laser ◽

Multiscale Simulation ◽

Experimental Methodology ◽

Computational Domain ◽

Area Of Interest ◽

Depth Analysis ◽

Laser Solid Interactions

A three-dimensional, thermal-structural finite element model, originally developed for the study of laser–solid interactions and the generation and propagation of surface acoustic waves in the macroscopic level, was downscaled for the investigation of the surface roughness influence on pulsed laser–solid interactions. The dimensions of the computational domain were reduced to include the laser-heated area of interest. The initially flat surface was progressively downscaled to model the spatial roughness profile characteristics with increasing geometrical accuracy. Since we focused on the plastic and melting regimes, where structural changes occur in the submicrometer scale, the proposed downscaling approach allowed for their accurate positioning. Additionally, the multiscale simulation results were discussed in relation to experimental findings based on white light interferometry. The combination of this multiscale modeling approach with the experimental methodology presented in this study provides a multilevel scientific tool for an in-depth analysis of the influence of heat parameters on the surface roughness of solid materials and can be further extended to various laser–solid interaction applications.

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