超短脉冲超强激光等离子体中新的能量吸收机制

NEW ENERGY ABSORPTION MECHANISMS IN PLASMAS PRODUCED BY ULTRASHORT ULTRAINTENSE LASER PULSES

介绍了超短脉冲超强激光等离子体中几种新的能量吸收机制．强激光照射等离子体时，相对论效应导致电子质量增大，相对论电子等离子体频率减小，激光能更深地进入等离子体产生强烈吸收．结合二维粒子模拟结果，着重介绍了真空加热和Ｊ×Ｂ加热这两种重要的能量吸收机制，粒子模拟结果清晰地描述了这两种吸收机制．

New energy absorption mechanisms in plasmas produced by ultrashort ultraintense laser pulses are described.The laser is so bright that the relativistic effect increases electron mass,and the lowering of plasma frequency enables the laser to penetrate into the overdense plasma and strong absorption occurs.The mechanisms,such as vacuum heating and J×B heating,are discussed via two-dimensional particle simulations, which clearly indicate both absorption types.