Gupta Devki Nandan, Nam In Hyuk, Suk Hyyong
Department of Physics and Astrophysics, University of Delhi, Delhi, India.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Nov;84(5 Pt 2):056403. doi: 10.1103/PhysRevE.84.056403. Epub 2011 Nov 4.
A laser-driven plasma beat wave, propagating through a plasma with a periodic density modulation, can generate two sideband plasma waves. One sideband moves with a smaller phase velocity than the pump plasma wave and the other propagates with a larger phase velocity. The plasma beat wave with a smaller phase velocity can accelerate modest-energy electrons to gain substantial energy and the electrons are further accelerated by the main plasma wave. The large phase velocity plasma wave can accelerate these electrons to higher energies. As a result, the electrons can attain high energies during the acceleration by the plasma waves in the presence of a periodic density modulation. The analytical results are compared with particle-in-cell simulations and are found to be in reasonable agreement.
由激光驱动的等离子体拍频波，在具有周期性密度调制的等离子体中传播时，会产生两个边带等离子体波。一个边带的相速度比泵浦等离子体波小，另一个边带的相速度比泵浦等离子体波大。相速度较小的等离子体拍频波能够将中等能量的电子加速以获得可观的能量，并且这些电子会被主等离子体波进一步加速。相速度较大的等离子体波能够将这些电子加速到更高的能量。因此，在存在周期性密度调制的情况下，电子在被等离子体波加速的过程中能够获得高能量。将解析结果与粒子模拟结果进行了比较，发现二者吻合得较为合理。
