Laser-Driven and Magnetized Ultracold Neutral Plasmas

激光驱动和磁化超冷中性等离子体

基本信息

批准号：
2107709
负责人：
Thomas Killian
金额：
$ 52.84万
依托单位：
William Marsh Rice University
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-05-15 至 2025-04-30
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2107709&HistoricalAwards=false
关键词：
Laser Driven Magnetized Ultracold Neutral

项目摘要

This project will explore the fundamental behavior of a plasma, a soup of electrons and ions, in a virtual ‘magnetic bottle’ trap. In order to understand how the magnetic field of the Earth protects life from electrically charged particles streaming from the sun, or to generate clean energy from nuclear fusion, one has to understand how a plasma behaves in a magnetic field. This is one of the key problems in the field of plasma physics. This project will provide a detailed understanding of the behavior of plasmas trapped by a magnetic field. The plasma will be created in a highly controlled manner that results in an ultracold plasma, which is colder than outer space. Such low temperatures make it easier to isolate different processes in the system for study, such as the rate at which particles escape from the trap. Surprisingly, an ultracold plasma shows behavior that is similar to hot and dense astrophysical plasmas, so these experiments can answer fundamental questions on the properties of objects such as white dwarf stars, which can possess strong magnetic fields. The project will also train students in a broad set of technical skills so they can contribute to the STEM workforce. Outreach and recruiting efforts will be pursued in order to increase participation by students from diverse backgrounds.This project will combine recently developed tools for laser cooling ions in an ultracold neutral plasma (UCNP) with magnetic-confinement techniques. This offers exciting opportunities for discovery plasma science, such as characterizing equilibration and transport phenomena in crossover regimes of magnetization and Coulomb-interaction (or ‘coupling’) strength. Combining laser and magnetic forces may provide a solution for long-standing challenges to plasma confinement in a quadrupole magnetic-field geometry, namely the escape of plasma through loss gaps along field lines. The combination of strong coupling and magnetization modifies transport phenomena and collective modes, and has attracted increasing interest from the dusty and high-energy-density plasma communities. These experiments will create a new system for probing this physics, and will test recent theories describing collisional processes in this regime. The specific goals are to (1) characterize the loss processes and scaling of magnetic confinement times with magnetic field for UCNPs formed in a quadrupole magnetic field, (2) measure the self-diffusion constant for magnetized ions and observe effects of strong coupling, and (3) use laser forces to plug loss gaps that typically allow plasma to escape along guiding-center magnetic field lines in a quadrupole magnetic field, creating long-term confinement.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.

该项目将探索虚拟“磁瓶”陷阱中等离子体（电子和离子汤）的基本行为，以了解地球磁场如何保护生命免受来自太阳或地球的带电粒子的影响。为了通过核聚变产生清洁能源，人们必须了解等离子体在磁场中的行为，这是等离子体物理学领域的关键问题之一，该项目将详细了解被等离子体捕获的等离子体的行为。将产生等离子体。以高度受控的方式产生超冷等离子体，这种低温使得分离系统中的不同过程进行研究变得更加容易，例如粒子从陷阱中逃逸的速率。超冷等离子体表现出与热而致密的天体物理等离子体相似的行为，因此这些实验可以回答有关白矮星等物体性质的基本问题，这些物体可能具有强磁场，该项目还将对学生进行广泛的培训。技术技能，所以他们可以为 STEM 劳动力做出贡献。我们将开展外展和招聘工作，以增加来自不同背景的学生的参与。该项目将结合最近开发的超冷中性等离子体 (UCNP) 中激光冷却离子的工具与磁约束技术。这为发现等离子体科学提供了令人兴奋的机会，例如表征磁化强度和库仑相互作用（或“耦合”）强度交叉范围内的平衡和传输现象，可以为长期存在的挑战提供解决方案。强耦合和磁化的结合改变了输运现象和集体模式，并引起了尘埃和高能领域越来越多的兴趣。这些实验将创建一个新的系统来探测这种物理现象，并将测试描述该区域碰撞过程的最新理论，具体目标是（1）表征磁场的磁约束时间的损失过程和缩放。 UCNP 成立在四极磁场中，(2) 测量磁化离子的自扩散常数并观察强耦合的影响，以及 (3) 使用激光力来堵塞通常允许等离子体沿引导中心磁场线逃逸的损耗间隙四极磁场，产生长期限制。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。