Theoretical and Experimental Study of the Influence of Orbital Angular Momentum of Light on High-Intensity Laser-Plasma Interactions

这个项目关注光的一个基本物理特性--其轨道角动量(OAM)。带有OAM的激光束的一个特征是扭曲的波前，形状为螺旋线。OAM在高强度激光-等离子体相互作用中的作用仍然知之甚少，该项目将通过一个专门的计算研究计划来解决这个问题，该计划与欧洲旗舰激光设施的实验相耦合。位于罗马尼亚和捷克共和国的极光基础设施(ELI)激光设施拥有一些世界上最强大的激光。该项目将探索产生高强度螺旋激光脉冲的新方法，以及促进激光脉冲和等离子体之间的OAM交换的新方法。具体地说，目的是通过计算建模来确定OAM交换对激光驱动离子加速的影响，并在ELI设施中对模型的结果进行实验测试。这项探索性研究将为在罗马ELI-NP设施利用螺旋光束进行新型核物理和强场实验的长期研究计划铺平道路。在高强度激光-物质相互作用的背景下，大多数激光改进都集中在增加功率、靶上强度、总能量和压缩脉冲的对比度上。然而，偏振光还有另一个基本特征--角动量。轨道角动量与方位角相位相关，因此它与偏振无关，并且可以通过产生具有扭曲波前的激光来显著增强。这个项目是一个合作项目，旨在通过将携带螺旋光子束的OAM推向相对论强度，并研究它们与相对论等离子体的角动量交换，来探索光-物质相互作用的前沿。该项目将在罗马尼亚新的1PW CETAL激光器和1PW和10PW ELI-NP激光器设施中，将理论和模拟研究与专门的实验计划结合起来。该项目将确定OAM交换对激光驱动的离子加速的影响，以及有效地利用短激光脉冲产生扭曲的质量推动力的条件。后者在适合控制带电粒子传输的等离子体中产生持久的体积磁场。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project focuses on a fundamental physics characteristic of light - its orbital angular momentum (OAM). A signature of a laser beam with OAM is a twisted wave-front that is shaped as a helix. The role of OAM in high-intensity laser-plasma interactions is still poorly understood and this project will address it through a dedicated computational research program that couples to experiments at flagship European laser facilities. The Extreme Light Infrastructure (ELI) laser facilities located in Romania and in the Czech Republic have some of the most powerful lasers in the world. The project will explore new methods for creating high-intensity helical laser pulses and new methods that facilitate the exchange of OAM between a laser pulse and a plasma. Specifically, the aim is to determine the impact of the OAM exchange on laser-driven ion acceleration via computational modeling, and to experimentally test the results of the models at the ELI facilities. This exploratory research will pave the way towards a long term research program of utilizing helical light beams for novel nuclear physics and strong-field experiments at the ELI-Nuclear Physics (ELI-NP) facility in Romania.In the context of high-intensity laser-matter interactions, most of the laser improvements have been focused on increasing power, on-target intensity, total energy, and the contrast of the compressed pulse. There is however another fundamental characteristic of polarized light - its angular momentum. The orbital angular momentum is associated with an azimuthal phase dependence, so it is independent of the polarization and can be significantly enhanced by generating a laser beam with twisted wave-fronts. This project is a collaborative program with an aim to explore the frontiers of light-matter interaction by pushing the OAM carrying helical photon beams to relativistic intensities and investigating their exchange of angular momentum with relativistic plasmas. This project will combine theoretical and simulation research with a dedicated experimental program at the new 1 petawatt (PW) CETAL laser and 1 PW and 10 PW ELI-NP laser facilities in Romania. The project will determine the impact of the OAM exchange on laser-driven ion acceleration and the conditions for effectively generating a twisted pondermotive force by short laser pulses. The latter generates a long-lasting volumetric magnetic field in a plasma suitable for controlling charged particle transport.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.