Magnetizing a Complex Plasma without a Magnetic Field

26.01.2015

In recent years, complex plasmas have enabled researchers to study the physics of strongly correlated plasmas on the individual particle level. So far, however, these studies were limited to partially magnetized plasmas, where only the electrons and, very recently, the ions could be magnetized. Writing in Physical Review Letters, Hanno Kählert, Hartmut Löwen (HHU Düsseldorf) together with Michael Bonitz (ITAP, CAU Kiel) and Alexander Piel and coworkers (IEAP, CAU Kiel) now report a new method that allows the "magnetization" of the heavy dust particles. They propose to replace the Lorentz force acting on charged particles in a magnetic field by the equivalent Coriolis force experienced by particles in a rotating reference frame. 

The theoretical analysis shows that this can be realized by rotating the neutral gas in a complex plasma, which causes the dust particles to co-rotate with the gas. Experiments with rotating dust clusters by Jan Carstensen and Franko Greiner (IEAP,CAU Kiel) fully confirmed the theoretical predictions. The figure shows the normal mode frequencies of a small two-dimensional dust cluster (symbols) and their dependence on the rotation frequency, which are in excellent agreement with the theoretical model (i.e. magnetized, non-rotating system, solid lines).

This work is a collaboration of the SFB-TR24 and SFB-TR6

Paper: "Magnetizing a complex plasma without a magnetic field" by H. Kählert, J. Carstensen, M. Bonitz, H. Löwen, F. Greiner, and A. Piel, Physical Review Letters 109, 155003 (2012)