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.
