Researchers at U.C. San Diego have succeeded in trapping plasma with a combination of static electric and magnetic fields. An article in the February issue of Physics Today describes the trap, and the surprising and novel vortex crystals that formed when the plasma was allowed to cool. Plasma, considered the fourth state of matter, is an ionized gas composed of equal parts of positive and negative ions. The UCSD researchers, sponsored in part by ONR, focused on non-neutral plasma, which consists entirely of positive or negative ions.

Theoretically, this type of plasma can be confined forever in a thermally stable, quiescent state. These simple plasma systems are providing detailed experimental work to test long-held theories in plasma physics and fluid dynamics. This work may also hold the key to high-precision atomic clocks, quantum computing, cold positron beams and the creation of anti-hydrogen.