TY - JOUR
T1 - High-harmonic generation in plasmas by relativistic Thomson scattering
AU - Banerjee, S.
AU - Valenzuela, A. R.
AU - Shah, R. C.
AU - Maksimchuk, A.
AU - Umstadter, D.
N1 - Funding Information:
This work is sup p orted by the Chemical Sciences, Geosciences and Biosciences Division of the Office of Basic Energy Sciences, Office of Science, US Department of Energy and the National Science Foundation.
PY - 2002/11/20
Y1 - 2002/11/20
N2 - Results are presented on the generation of high harmonics due to the scattering of relativistic electrons from high-intensity laser light. The experiments are carried out with a Nd:glass laser system with a peak intensity of 1019W cm-2 in underdense He, N2 and Ar plasma. It is shown that, at high intensities when the normalized electric field approaches unity, in addition to the conventional atomic harmonics from bound electrons, there is significant contribution to the harmonic spectrum from free electrons. The characteristic signatures of this are found to be the emission of even-order harmonics, a linear dependence on the electron density, a significant amount of harmonics even with circular polarization and a much smaller spatial region over which these harmonics are produced as compared to the atomic case. Imaging of the harmonic beam shows that it is emitted in a narrow cone with a divergence of 2-3°. The measured spatial profile of the harmonics is shown to be in excellent agreement with calculations, which assume that electrons with relativistic energies play a significant part in the scattering process.
AB - Results are presented on the generation of high harmonics due to the scattering of relativistic electrons from high-intensity laser light. The experiments are carried out with a Nd:glass laser system with a peak intensity of 1019W cm-2 in underdense He, N2 and Ar plasma. It is shown that, at high intensities when the normalized electric field approaches unity, in addition to the conventional atomic harmonics from bound electrons, there is significant contribution to the harmonic spectrum from free electrons. The characteristic signatures of this are found to be the emission of even-order harmonics, a linear dependence on the electron density, a significant amount of harmonics even with circular polarization and a much smaller spatial region over which these harmonics are produced as compared to the atomic case. Imaging of the harmonic beam shows that it is emitted in a narrow cone with a divergence of 2-3°. The measured spatial profile of the harmonics is shown to be in excellent agreement with calculations, which assume that electrons with relativistic energies play a significant part in the scattering process.
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U2 - 10.1080/0950034021000011509
DO - 10.1080/0950034021000011509
M3 - Article
AN - SCOPUS:0037146535
SN - 0950-0340
VL - 49
SP - 2599
EP - 2614
JO - Journal of Modern Optics
JF - Journal of Modern Optics
IS - 14-15
ER -