Laser-Plasma Interactions at the Intensity Frontier: the Transition to the QED-Plasma Regime

强度前沿的激光-等离子体相互作用：向 QED-等离子体体系的过渡

• 批准号: EP/M018156/1
• 负责人: Christopher Ridgers
• 金额: $ 45.66万
• 依托单位: University of York
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FM018156%2F1
• 关键词: Laser; Plasma; Interactions; Intensity; Frontier

Current high-power lasers focus light to intensities up to 10^23 times higher than the intensity of sunlight at the surface of the Earth. At these extreme intensities the electrons are quickly stripped from the atoms in any matter in the laser focus, generating a plasma. However, as intensities increase from the peak reached today (2x10^22W/cm^2) to those expected to be reached on next-generation facilities such as the Extreme Light Infrastructure (>10^23W/cm^2), due to become operational by 2017, the behaviour of this plasma dramatically alters. At intensities >5x10^22W/cm^-2 the electromagnetic fields in the laser focus are predicted to accelerate the electrons in the plasma so violently that they prolifically radiate gamma-ray photons. These photons can carry away so much energy that the electron's motion is affected by the resulting energy loss and the radiation reaction force (the force the particle exerts on itself as it radiates) becomes significant in determining the plasma's macroscopic dynamics. The laser's electromagnetic fields are so strong that quantum electrodynamics effects also become important. In this case the radiation reaction force no longer behaves deterministically, i.e. instead of knowing the electron's trajectory exactly as in the classical picture, we now can only know the probability that the electron has a given trajectory. In addition, the gamma-ray photons can be converted into electron-positron pairs, these pairs can emit further photons which emit more pairs and an avalanche of antimatter production can ensue with strong consequences for the behaviour of the plasma as a whole. The interplay of radiation reaction, QED effects and ultra-relativistic plasma processes will define the physics of laser-matter interactions in this new 'QED-plasma' regime, but is currently poorly understood. We will elucidate the basic theory of laser propagation and absorption in QED-plasmas. This will provide the foundational theory describing laser matter interactions moving beyond today's intensity frontier and into the foreseeable future. This theory will be underpinned by experiments measuring the rates of the important QED processes for the first time. The new theory will then be used to design the first experiments to generate a QED plasma in the laboratory. This project will culminate in the first generation of a QED-plasma, usually only seen in extreme astrophysical environments such as pulsar magnetospheres, in the laboratory.

目前的高功率激光器将光聚焦到比地球表面的太阳光强度高10^23倍的强度。在这些极端强度下，电子迅速从激光焦点中任何物质的原子中剥离，产生等离子体。然而，随着强度从今天达到的峰值（2 × 10^22 W/cm ^2）增加到下一代设施（如极端光基础设施）预计将达到的水平（> 10^23 W/cm ^2），由于到2017年投入使用，这种等离子体的行为发生了显着变化。当强度大于5 × 10^22 W/cm^-2时，激光焦点中的电磁场预计会对等离子体中的电子进行剧烈加速，从而大量辐射出伽马射线光子。这些光子可以带走如此多的能量，以至于电子的运动受到由此产生的能量损失的影响，并且辐射反作用力（粒子在辐射时施加在自身上的力）在确定等离子体的宏观动力学方面变得重要。激光的电磁场如此之强，以至于量子电动力学效应也变得重要。在这种情况下，辐射反作用力不再具有确定性，也就是说，我们现在只能知道电子具有给定轨迹的概率，而不是像经典图像中那样精确地知道电子的轨迹。此外，伽马射线光子可以转换成电子-正电子对，这些对可以发射更多的光子，这些光子可以发射更多的对，并且反物质的雪崩产生可以对整个等离子体的行为产生强烈的后果。辐射反应，QED效应和超相对论等离子体过程的相互作用将定义在这个新的“QED等离子体”制度的激光-物质相互作用的物理，但目前知之甚少。我们将阐明激光在QED等离子体中传输和吸收的基本理论。这将提供基础理论，描述激光物质相互作用超越今天的强度前沿，并进入可预见的未来。这一理论将通过首次测量重要QED过程速率的实验得到支持。然后，新理论将用于设计第一个实验，以在实验室中产生QED等离子体。该项目将在第一代QED等离子体中达到高潮，通常只在实验室中的脉冲星磁层等极端天体物理环境中看到。

项目成果

Reaching supercritical field strengths with intense lasers

• DOI: 10.1088/1367-2630/ab1e0d
• 发表时间: 2018-07
• 期刊: New Journal of Physics
• 影响因子: 3.3
• 作者: T. Blackburn;A. Ilderton;M. Marklund;Christopher Ridgers

Realising single-shot measurements of quantum radiation reaction in high-intensity lasers

• DOI: 10.1088/1367-2630/ab1baf
• 发表时间: 2018-04
• 期刊: New Journal of Physics
• 影响因子: 3.3
• 作者: C. Baird;C. Murphy;T. Blackburn;A. Ilderton;S. Mangles;M. Marklund;C. Ridgers

Potential to measure quantum effects in recent all-optical radiation reaction experiments

• DOI: 10.1117/12.2520591
• 发表时间: 2019-04
• 作者: Christopher Arran;J. M. Cole;E. Gerstmayr;T. Blackburn;S. Mangles;C. Ridgers

Optimal parameters for radiation reaction experiments

• DOI: 10.1088/1361-6587/ab20f6
• 发表时间: 2019-07-01
• 期刊: PLASMA PHYSICS AND CONTROLLED FUSION
• 影响因子: 2.2
• 作者: Arran, C.;Cole, J. M.;Ridgers, C. P.
• 通讯作者: Ridgers, C. P.

Experimental Evidence of Radiation Reaction in the Collision of a High-Intensity Laser Pulse with a Laser-Wakefield Accelerated Electron Beam

• DOI: 10.1103/physrevx.8.011020
• 发表时间: 2018-02-07
• 期刊: PHYSICAL REVIEW X
• 影响因子: 12.5
• 作者: Cole, J. M.;Behm, K. T.;Mangles, S. P. D.
• 通讯作者: Mangles, S. P. D.