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arXiv · 1511.00777

Insight of breaking of powerful axisymmetrically-polarized laser pulses in under-dense plasma

Nobuhiko Nakanii·Tomonao Hosokai·Naveen C. Pathak·Shinichi Masuda·Alexei G. Zhidkov·Hiroki Nakahara·Kenta Iwasa·Yoshio Mizuta·Naoki Takeguchi·Takamitsu P. Otsuka·Keiichi Sueda·Hirotaka Nakamura·Michiaki Mori·Masaki Kando·Ryosuke Kodama
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Abstract

Interaction of axisymmetrically-polarized (radially or azimuthally-polarized), relativistically intense laser pulses (ALP) with under-dense plasma is shown experimentally to be different from the interaction of conventional Gaussian pulses. The difference is clearly observed in distinct spectra of scattered laser light as well as in appearance of a strong side emission of second harmonic in the vicinity of focus spot. According 3D particle-in-cell simulations, this is a result of instability in the propagation of ALP in under-dense plasma. Laser wakefield acceleration of electrons by ALP, therefore, is less efficient than that by Gaussian laser pulses but ALP may be interesting for efficient electron self-injection.

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Nobuhiko Nakanii, Tomonao Hosokai, Naveen C. Pathak, Shinichi Masuda, Alexei G. Zhidkov, Hiroki Nakahara, Kenta Iwasa, Yoshio Mizuta, Naoki Takeguchi, Takamitsu P. Otsuka, Keiichi Sueda, Hirotaka Nakamura, Michiaki Mori, Masaki Kando, Ryosuke Kodama. 2015-11-03. Insight of breaking of powerful axisymmetrically-polarized laser pulses in under-dense plasma. https://doi.org/10.1103/physreve.94.063205

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