通过低相干激光高效产生热电子
Efficient hot electron generation via low-coherence lasers
AI总结：
研究通过利用两种带宽的瞬时低相干激光，在特定强度和能量条件下增强热电子产生，相比窄带激光，宽带激光显著提高热电子温度、硬X射线产量及能量转换效率，验证中带宽激光是高效热电子源并支持产生明亮X射线源。
AI中文摘要：
激光产生的等离子体中产生的热电子是惯性约束聚变、实验室天体物理学和高能密度物理的核心研究对象。这些电子源于非线性激光 - 等离子体相互作用中的不稳定性，而激光带宽对其有关键调制作用。在此，我们通过实验证明，利用两种带宽（0.2%和0.6%）的瞬时低相干激光，在强度为2 - 8×10¹⁴W/cm²、能量高达620J的条件下，能增强热电子的产生。与传统窄带激光相比，宽带激光能显著提高热电子温度和硬X射线产量。结果表明，0.6%宽带激光的热电子能量转换效率比窄带激光高约4倍，最高可达2.8%。这些发现验证了中带宽激光作为高效热电子源的有效性，并支持在高能密度物理中产生用于先进成像的明亮X射线源。
英文摘要：
Hot electrons generated in laser-produced plasmas are a central focus in inertial confinement fusion, laboratory astrophysics, and high-energy-density physics. These electrons originate from instabilities in nonlinear laser-plasma interactions, which are critically modulated by laser bandwidth. Here, we experimentally demonstrate enhanced generation of hot electrons by utilizing instantaneous low-coherence lasers with two bandwidths (0.2% and 0.6%) at intensities of 2-8x10^{14} W/cm^2 and energies up to 620 J. A significant enhancement of hot electron temperature and hard X-ray yield is observed with the broadband lasers compared to a conventional narrowband laser. The results show that the hot electron energy conversion efficiency of the 0.6% broadband laser is approximately 4 times higher than that of the narrowband laser, reaching a maximum value of 2.8%. These findings validate a moderate-bandwidth laser as an efficient hot electron source and support the generation of bright X-ray sources for advanced imaging in high-energy-density physics.
