Coherent Thomson backscattering from laser-driven relativistic ultra-thin electron layers
Coherent Thomson backscattering from laser-driven relativistic ultra-thin electron layers
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DOI：
10.1140/epjd/e2009-00081-1
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发表时间：
2009-11-01
影响因子：
1.8
通讯作者：
Wu, H. -C.
中科院分区：
文献类型：
--
作者：
Meyer-ter-Vehn, J.;Wu, H. -C.
应用解析理论和一维细胞内粒子模拟，讨论了超薄薄膜中激光驱动致密相对论电子层的产生及其在相干汤姆逊后向散射中的应用。探索了在直接激光作用下，所有箔电子与离子分离的爆破制度。电子跟随光波接近其前端。单电子解决方案应用于初始加速、相位切换和第二级助推。相干反射光显示多普勒位移光谱，啁啾在几个八度。发现多普勒频移为gamma(x) (2)=1/(1-beta(x)(2))，其中beta(x)为电子层法向的电子速度分量，也是驱动激光脉冲的方向。由于横向电子动量p(y)，多普勒频移4 γ (x) (2)=4 γ (2)/(1+(p（y)/mc)(2)）千分之一2 γ明显小于4 γ(2)的全频移。提出了扭转p(y)->和恢复全多普勒频移的方法，并通过1D-PIC仿真进行了验证。这些方法开辟了设计强单阿秒脉冲的新途径。
The generation of laser-driven dense relativistic electron layers from ultra-thin foils and their use for coherent Thomson backscattering is discussed, applying analytic theory and one-dimensional particle-in-cell simulation. The blow-out regime is explored in which all foil electrons are separated from ions by direct laser action. The electrons follow the light wave close to its leading front. Single electron solutions are applied to initial acceleration, phase switching, and second-stage boosting. Coherently reflected light shows Doppler-shifted spectra, chirped over several octaves. The Doppler shift is found ae gamma(x) (2)=1/(1-beta(x) (2)), where beta(x) is the electron velocity component in normal direction of the electron layer which is also the direction of the driving laser pulse. Due to transverse electron momentum p(y), the Doppler shift by 4 gamma(x) (2)=4 gamma(2)/(1+(p(y)/mc)(2))a parts per thousand 2 gamma is significantly smaller than full shift of 4 gamma(2). Methods to turn p(y)-> 0 and to recover the full Doppler shift are proposed and verified by 1D-PIC simulation. These methods open new ways to design intense single attosecond pulses.