通过时空光学涡旋调制产生孤立准直偏振γ射线束
Generation of Isolated Collimated Polarized $γ$-ray Beams via Spatiotemporal Optical Vortex Modulation
- State Key Laboratory of Ultra-Intense Laser Science and Technology, Shanghai Institute of Optics and Fine Mechanics (SIOM), Chinese Academy of Sciences (CAS)（中国科学院上海光学精密机械研究所）
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences（中国科学院大学材料科学与光电技术学院）
- Laboratory of Zhongyuan Light, School of Physics, Zhengzhou University（郑州大学物理学院中原之光实验室）
- State Key Laboratory of Dark Matter Physics, Key Laboratory for Laser Plasmas (MoE), School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院激光等离子体教育部重点实验室暗物质物理国家重点实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究提出用线偏振时空光学涡旋激光脉冲辐照固体箔的新方案，通过粒子模拟实现了孤立准直、高偏振的阿秒γ射线束，为相关物理领域提供了可行的光源方案。
AI中文摘要：
核物理、天体物理和高能物理领域对阿秒级、准直、高亮度、偏振的γ射线源有迫切需求，但由于光束捕获与辐射动力学之间存在固有权衡，在单一孤立源中同时实现阿秒级持续时间、高准直度、高亮度和高偏振度仍是一项未解决的挑战。本文提出一种新方案，利用实验室可获得的线偏振时空光学涡旋（STOV）激光脉冲辐照常规固体箔，产生孤立、准直、高亮度、偏振的阿秒γ射线束。三维自旋分辨粒子模拟显示，该相对论强度的STOV脉冲可在其时空奇点处捕获并加速电子，形成紧凑的孤立电子束团；该电子束团随后与反射激光脉冲对头碰撞，通过非线性康普顿散射产生孤立γ射线束。在峰值强度为7×10²¹ W/cm²的条件下，研究人员观测到孤立准直（约1.5°）的γ射线束，其平均线偏振度>60%，持续时间约500阿秒。该方法可在当前或未来激光装置上实现，且对激光和靶参数的变化具有鲁棒性，凸显了时空结构化光场调制解决等离子体物理领域未解决问题的能力。
英文摘要：
Attosecond, collimated, bright, polarized $γ$-ray sources are in high demand across nuclear physics, astrophysics, and high-energy physics. However, realizing attosecond duration, high collimation, high brilliance, and high polarization simultaneously within a single isolated source remains an outstanding challenge, owing to the inherent trade-offs between beam trapping and radiative dynamics. Here, we propose a novel scheme to generate an isolated, collimated, high-brilliance, polarized attosecond $γ$-ray beam from conventional solid foils irradiated by a linearly polarized spatiotemporal optical vortex (STOV) laser pulse accessible in Lab. Three-dimensional spin-resolved particle-in-cell simulations reveal that this relativistic-intensity STOV pulse can trap and accelerate electrons at its spatiotemporal singularity, producing a compact isolated electron bunch. This electron bunch subsequently undergoes head-on collision with the reflected laser pulse, which generates isolated $γ$-ray beams through nonlinear Compton scattering. With a peak intensity of $7\times10^{21}$ W/cm$^2$, we observe an isolated collimated ($\sim1.5^{\circ}$) $γ$-ray beam with an average linear polarization of $>60\%$ and a duration of $\sim$500 attoseconds. This approach is feasible with current or upcoming laser facilities and robust against variations in laser and target parameters, highlighting the capability of spatiotemporal structured light field modulation to address outstanding problems in plasma physics.
