Laser Plasma Interactions: Fusion, Particle Acceleration and Other Applications

激光等离子体相互作用：聚变、粒子加速和其他应用

• 批准号: RGPIN-2019-05013
• 负责人: Fedosejevs, Robert
• 金额: $ 3.64万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714920
• 关键词: Laser; Plasma; Interactions; Fusion; Particle

The proposed research will investigate high intensity ( 10^18 to 10^21 W/cm2) laser-plasma interactions in the relativistic regime for MeV electron and MeV proton production and low intensity laser-plasma interactions using Laser Induced Breakdown Spectroscopy (LIBS) for detection of heavy metal contamination in drinking water. The former investigations target a number of applications, including: (1) fusion energy where such MeV particles can be used for Fast Ignition of Laser Fusion in a compressed fuel pellet, significantly reducing the required laser system energies from the standard self ignition approaches and (2) super compact laser driven MeV particle sources for applications in (a) subpicosecond radiography, (b) radioisotope production (c) proton cancer therapy and Fast Ignition drivers for Laser Fusion Energy systems. The low intensity investigations are targeted at developing field portable laser based systems for measurements of water quality, specifically heavy metal contamination, in remote locations and third world countries. One of the novel approaches we are exploring for the high intensity laser plasma applications is the use of newly developed Orbital Angular Mode (OAM) or "Vortex" mode optical pulses which carry extra angular momentum in Laguerre-Gaussian beams. This extra angular momentum can be coupled into the electrons in the plasma when the light is absorbed driving a circular current and generating Megagauss strength axial magnetic fields. While these fields have been predicted in a number of theoretical investigations, there are no experimental measurements verifying these predictions. We have developed a simple technique to generate such OAM modes in high intensity laser systems by the insertion of a specially designed spiral staircase mirror as one of the final turning mirrors prior to focusing the light onto targets. We have successfully implemented such mirrors in collaborations with the Center for Intense Pulsed Lasers (CLPU) in Salamanca Spain in preliminary experiments with their 200 Terawatt (TW) laser system. Such powerful magnetic fields could lead to enhanced guiding of electrons in high density plasma which would be very important for applications in Fast Ignition of Laser Fusion Energy systems. In addition we will study the propagation of proton and electron beams in solid density plasmas (called warm dens matter) of relevance to the interior of stars and laser fusion ignition and burn physics and Thomson scattering of high intensity pulses from individual electrons which can then be used as a peak intensity diagnostic for laser beams. We are also developing the next generation of efficient diode pumped high power (multi-TW) lasers systems, suitable for real scientific and industrial applications. This includes both picosecond ceramic disk based chirped pulse amplification (CPA) Yb:YAG lasers and femtosecond Optical Parametric Chirped pulse amplification lasers.

拟议的研究将研究 MeV 电子和 MeV 质子产生的相对论范围内的高强度（10^18 至 10^21 W/cm2）激光-等离子体相互作用，以及使用激光诱导击穿光谱（LIBS）的低强度激光-等离子体相互作用饮用水中重金属污染检测。先前的研究针对许多应用，包括：（1）聚变能源，其中此类 MeV 粒子可用于压缩燃料芯块中激光聚变的快速点火，从而显着降低标准自点火方法所需的激光系统能量，以及（ 2) 超紧凑型激光驱动 MeV 粒子源，适用于 (a) 亚皮秒射线照相、(b) 放射性同位素生产、(c) 质子癌症治疗和激光聚变能源系统的快速点火驱动器。低强度调查的目标是开发基于现场便携式激光的系统，用于测量偏远地区和第三世界国家的水质，特别是重金属污染。 我们正在探索的高强度激光等离子体应用的新颖方法之一是使用新开发的轨道角模式（OAM）或“涡旋”模式光脉冲，它们在拉盖尔高斯光束中携带额外的角动量。 当光被吸收时，这种额外的角动量可以耦合到等离子体中的电子中，驱动环形电流并产生兆高斯强度的轴向磁场。 虽然在许多理论研究中已经预测了这些场，但没有实验测量来验证这些预测。我们开发了一种简单的技术，通过在将光聚焦到目标上之前插入专门设计的螺旋阶梯镜作为最终转动镜之一，在高强度激光系统中生成此类 OAM 模式。我们与西班牙萨拉曼卡强脉冲激光中心 (CLPU) 合作，通过其 200 太瓦 (TW) 激光系统的初步实验，成功实现了此类反射镜。如此强大的磁场可以增强高密度等离子体中电子的引导，这对于激光聚变能系统的快速点火应用非常重要。此外，我们还将研究质子和电子束在与恒星内部相关的固体密度等离子体（称为热密度物质）中的传播、激光聚变点火和燃烧物理以及来自单个电子的高强度脉冲的汤姆逊散射，然后可以将其用作激光束的峰值强度诊断。 我们还在开发下一代高效二极管泵浦高功率（多TW）激光器系统，适合真正的科学和工业应用。 这包括基于皮秒陶瓷盘的啁啾脉冲放大 (CPA) Yb:YAG 激光器和飞秒光学参量啁啾脉冲放大激光器。