Realising single-shot measurements of quantum radiation reaction in high-intensity lasers
Realising single-shot measurements of quantum radiation reaction in high-intensity lasers
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DOI：
10.1088/1367-2630/ab1baf
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发表时间：
2018-04
影响因子：
3.3
通讯作者：
C. Baird;C. Murphy;T. Blackburn;A. Ilderton;S. Mangles;M. Marklund;C. Ridgers
中科院分区：
文献类型：
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作者：
C. Baird;C. Murphy;T. Blackburn;A. Ilderton;S. Mangles;M. Marklund;C. Ridgers
现代激光技术现在已经足够先进，高强度激光脉冲和激光尾流场加速（LWFA）电子束之间的碰撞可以达到强场状态，因此可以测量光-物质相互作用的经典和量子状态之间的转变。然而，LWFA电子束的能谱在不同的镜头之间会有明显的波动，这使得很难清晰地分辨出辐射反应（RR）中的量子效应。在这里，我们展示如何这可以完成在只有一个单一的激光射击。毫米级的碰撞前漂移允许电子束扩展到比激光焦斑更大的尺寸，并在横向位置和角散度之间建立相关性。与之前的研究相反，这意味着对光束能量发散谱的测量可以自动区分光束中击中或错过激光焦斑的成分，从而产生和不产生共振。
Modern laser technology is now sufficiently advanced that collisions between high-intensity laser pulses and laser-wakefield-accelerated (LWFA) electron beams can reach the strong-field regime, so that it is possible to measure the transition between the classical and quantum regimes of light–matter interactions. However, the energy spectrum of LWFA electron beams can fluctuate significantly from shot to shot, making it difficult to clearly discern quantum effects in radiation reaction (RR), for example. Here we show how this can be accomplished in only a single laser shot. A millimetre-scale pre-collision drift allows the electron beam to expand to a size larger than the laser focal spot and develop a correlation between transverse position and angular divergence. In contrast to previous studies, this means that a measurement of the beam’s energy-divergence spectrum automatically distinguishes components of the beam that hit or miss the laser focal spot and therefore do and do not experience RR.