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arXiv · 0809.2224

Quasimonoenergetic electron beams produced by colliding cross-polarized laser pulses in underdense plasmas

C. Rechatin·J. Faure·A. Lifschitz·X. Davoine·E. Lefebvre·V. Malka
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Abstract

The interaction of two laser pulses in an underdense plasma has proven to be able to inject electrons in plasma waves, thus providing a stable and tunable source of electrons. Whereas previous works focused on the "beatwave" injection scheme in which two lasers with the same polarization collide in a plasma, this present letter studies the effect of polarization and more specifically the interaction of two colliding cross-polarized laser pulses. It is shown both theoretically and experimentally that electrons can also be pre-accelerated and injected by the stochastic heating occurring at the collision of two cross-polarized lasers and thus, a new regime of optical injection is demonstrated. It is found that injection with cross-polarized lasers occurs at higher laser intensities.

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C. Rechatin, J. Faure, A. Lifschitz, X. Davoine, E. Lefebvre, V. Malka. 2008-09-12. Quasimonoenergetic electron beams produced by colliding cross-polarized laser pulses in underdense plasmas. https://doi.org/10.1088/1367-2630%2F11%2F1%2F013011

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