Inverse bremsstrahlung heating beyond the first Born approximation for dense plasmas in laser fields
Inverse bremsstrahlung heating beyond the first Born approximation for dense plasmas in laser fields
复制标题
激光场中稠密等离子体的逆轫致辐射加热超越第一玻恩近似
DOI：
10.1088/1367-2630/14/6/065010
复制
发表时间：
2012
影响因子：
3.3
通讯作者：
V. Krainov
中科院分区：
文献类型：
--
作者：
M. Moll;M. Schlanges;T. Bornath;V. Krainov
逆韧致辐射加热是激光与物质相互作用中的一个重要过程，它涉及两种不同的相互作用：电子与激光场的相互作用和电子与离子的相互作用。这使得分析方法非常困难。在强激光场中IB加热速率的量子微扰方法中，通常考虑相对于电子-离子势的第一玻恩近似，而电场的影响则精确地在Volkov波函数中进行。本文采用屏蔽的电子-离子相互作用势，提出了微扰处理。作为一个新的结果，我们得到的动量依赖，角平均加热率在第一玻恩近似。数值结果进行了讨论，在很宽的场强范围内，和加热速率的线性近似的适用性条件进行了详细分析。在微扰级数中再进一步，我们考虑了第二玻恩近似中的跃迁振幅，这使我们能够计算加热速率达到相互作用强度的第三阶。
Inverse bremsstrahlung (IB) heating, an important process in the laser–matter interaction, involves two different kinds of interaction—the interaction of the electrons with the external laser field and the electron–ion interaction. This makes analytical approaches very difficult. In a quantum perturbative approach to the IB heating rate in strong laser fields, usually the first Born approximation with respect to the electron–ion potential is considered, whereas the influence of the electric field is taken exactly in the Volkov wave functions. In this paper, a perturbative treatment is presented adopting a screened electron–ion interaction potential. As a new result, we derive the momentum-dependent, angle-averaged heating rate in the first Born approximation. Numerical results are discussed for a broad range of field strengths, and the conditions for the applicability of a linear approximation for the heating rate are analyzed in detail. Going a step further in the perturbation series, we consider the transition amplitude in the second Born approximation, which enables us to calculate the heating rate up to the third order of the interaction strength.