Hydrodynamic simulation of subpicosecond laser interaction with solid-density matter
Hydrodynamic simulation of subpicosecond laser interaction with solid-density matter
复制标题
DOI：
10.1103/physreve.62.1202
复制
发表时间：
2000-07-01
影响因子：
2.4
通讯作者：
Hüller, S
中科院分区：
文献类型：
--
作者：
Eidmann, K;Meyer-ter-Vehn, J;Hüller, S
本文用流体动力学程序MULTI-FS研究了亚皮秒超短激光脉冲在宽强度范围（10（11）~ 10（17）W/cm ~ 2）内与初始冷固体物质的相互作用。拉米斯河Schmalz，and J Meyer-ter-Vehn，Comput.物理通信49，475（1988）]。超短脉冲的治疗的基本修改是在一个陡峭的梯度等离子体的麦克斯韦方程的解决方案，考虑电子和离子之间的非平衡，以及覆盖从固态到高温等离子体的广泛范围的电导率和热导率的模型。模拟进行了比较，在正常和斜入射与铝目标的吸收测量。通过适当选择电子-离子能量交换时间（其特征在于在冷固体Al中为10至20 ps）获得良好的一致性。此外，我们讨论的温度，压力和密度的强度标度，其中的激光能量被沉积在膨胀的等离子体，以及传播的热波和冲击波到固体。对于大于或等于150 fs的激光脉冲宽度在本文中考虑的固体密度的等容加热的物质的量是由在整个强度范围内的电子热波的深度。
The interaction of ultrashort subpicosecond laser pulses with initially cold and solid matter is investigated in a wide intensity range (10(11) to 10(17) W/cm(2)) by means of the hydrodynamic code MULTI-FS, which is an extension of the long pulse version of MULTI [R. Ramis, R. Schmalz, and J Meyer-ter-Vehn, Comput. Phys. Commun. 49, 475 (1988)]. Essential modifications for the treatment of ultrashort pulses are the solution of Maxwell's equations in a steep gradient plasma, consideration of the nonequilibrium between electrons and ions, and a model for the electrical and thermal conductivity covering the wide range from the solid state to the high temperature plasma. The simulations are compared with several absorption measurements performed with aluminum targets at normal and oblique incidence. Good agreement is obtained by an appropriate choice of the electron-ion energy exchange time (characterized by 10 to 20 ps in cold solid Al). In addition we discuss the intensity scaling of the temperature, of the pressure, and of the density, where the laser energy is deposited in the expanding plasma, as well as the propagation of the heat wave and the shock wave into the solid. For laser pulse durations greater than or equal to 150 fs considered in this paper the amount of isochorically heated matter at solid density is determined by the depth of the electron heat wave in the whole intensity range.