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arXiv · 1602.08682

The controllable super-high energetic electrons by external magnetic fields at relativistic laser-solid interactions in the presence of large scale pre-plasmas

D. Wu·S. I. Krasheninnikov·S. X. Luan·W. Yu
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Abstract

The two stage electron acceleration model [arXiv: 1512.02411 and arXiv: 1512.07546] is extended to the study of laser magnetized-plasmas interactions at relativistic intensities and in the presence of large-scale preformed plasmas. It is shown that the cut-off electron kinetic energy is controllable by the external magnetic field strength and directions. Further studies indicate that for a right-hand circularly polarized laser (RH-CP) of intensity $10^{20}\ \text{W}/\text{cm}^2$ and pre-plasma scale length $10\ \mu\text{m}$, the cut-off electron kinetic energy can be as high as $500\ \text{MeV}$, when a homogeneous external magnetic field of exceeding $10000\ \text{T}$ (or $B=\omega_{c}/\omega_0>1$) is loaded along the laser propagation direction, which is a significant increase compared with that $120\ \text{MeV}$ without external magnetic field. A laser front sharpening mechanism is identified at relativistic laser magnetized-plasmas interactions with $B=\omega_{c}/\omega_0>1$, which is responsible for these super-high energetic electrons.

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D. Wu, S. I. Krasheninnikov, S. X. Luan, W. Yu. 2016-02-28. The controllable super-high energetic electrons by external magnetic fields at relativistic laser-solid interactions in the presence of large scale pre-plasmas. https://doi.org/10.1088/1361-6587/aa69a9

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