Studies of Ultracold Plasma

到目前为止，等离子体是宇宙中最常见的物质形式，但通常是相当热的，特别是在实验室中创造的时候。该项目的研究人员开发了一种技术，从激光冷却原子开始产生超冷等离子体，他们测得的温度低于1K。这项工作将继续研究超冷等离子体在扩展到真空中时以及当它们被磁场限制在二维和三维空间时的性质。研究人员将研究磁场如何改变等离子体的集体性质，以及动力学是如何改变的。研究人员将开发技术来测量等离子体产生的高激发原子的分布，以在低温下测试该理论，该理论与捕获和研究反氢原子的努力有关。他们将研究等离子体中电子的蒸发，这将提供对非平衡系统的基本物理的洞察，非平衡系统在自然界中经常出现。这项研究是探索性的，研究以前从未被探索或理论上处理过的物理系统的状态。它位于原子物理和等离子体物理之间。更好地了解这些系统可能与行星和恒星内部发生的天体物理过程有关，也可能与惯性约束聚变有关。它们还为最先进的分子动力学模拟提供了一个试验场，这些模拟在许多物理和技术领域都有应用，包括国家安全。研究生和本科生将接受最先进的光学技术培训，并获得高真空、模拟、射频和数字电子以及基于计算机的数据采集方面的经验。他们所处的环境会让他们暴露在各种各样的物理环境中。

Plasma is by far the most common form of matter in the universe, but is usually quite hot, especially when created in the laboratory. The researchers of this project developed a technique that starts with laser-cooled atoms to produce ultracold plasmas, with temperatures that they have measured to less than 1 K. This work will continue to study the properties of ultracold plasmas, as they expand into vacuum, and when they are confined in two and three dimensions with magnetic fields. The researchers will investigate how magnetic fields modify the collective properties of the plasma and how dynamics are changed. The researchers will develop techniques to measure the distribution of highly excited atoms created by the plasma to test the theory at low temperatures, which bears on efforts to trap and study antihydrogen atoms. They will study the evaporation of electrons from the plasma, which will provide insight into the basic physics of non-equilibrium systems, which occur quite often in nature.This research is exploratory, investigating regimes of physical system that have not previously been explored, or theoretically treated. It resides at the boundary between atomic physics and plasma physics. Greater understanding of these systems may have relevance for astrophysical processes occurring in the interior of planets and stars, as well as for inertial confinement fusion. They also provide a testing ground for state-of-the-art molecular dynamics simulations, which have applications in many areas of physics and technology, including national security. Graduate and undergraduate students will be trained in state-of-the-art optical techniques, along with gaining experience with high vacuum, analog, RF, and digital electronics, and computer-based data acquisition. They will be in an environment that exposes them to a wide variety of physics.