Feng B, Qin C Y, Geng X S, Yu Q, Wang W Q, Wu Y T, Yan X, Ji L L, Shen B F
State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Sci Rep. 2019 Dec 11;9(1):18780. doi: 10.1038/s41598-019-55217-4.
We investigated the emission of multi-MeV γ-Ray beams with orbital angular momentum (OAM) from the interaction of an intense circularly polarized (CP) laser with a micro-channel plasma target. The driving laser can generate high energy electrons via direct laser acceleration within the channel. By attaching a plasma foil as the reflecting mirror, the CP laser is reflected and automatically colliding with the electrons. High energy gamma-photons are emitted through inverse Compton scattering (ICS) during collision. Three-dimensional particle-in-cell simulations reveal that the spin angular momentum (SAM) of the CP laser can be transferred to the OAM of accelerated electrons and further to the emitted gamma-ray beam. These results may guide future experiments in laser-driven gamma-ray sources using micro-structures.
我们研究了强圆偏振（CP）激光与微通道等离子体靶相互作用产生的具有轨道角动量（OAM）的多兆电子伏γ射线束的发射。驱动激光可通过通道内的直接激光加速产生高能电子。通过附加一个等离子体箔作为反射镜，CP激光被反射并自动与电子碰撞。碰撞过程中通过逆康普顿散射（ICS）发射出高能伽马光子。三维粒子模拟显示，CP激光的自旋角动量（SAM）可以转移到加速电子的OAM上，并进一步转移到发射的伽马射线束上。这些结果可能会为未来利用微结构的激光驱动伽马射线源实验提供指导。
