Traveling pairs of spots in a periodically driven gas discharge system: collective motion caused by interaction
We report on a new type of interaction between solitary current density spots observed in an ac-driven gas discharge system. These spots behave as independent particles as long as they are far apart from each other. Upon collision, in most cases one of the spots is extinguished. However, we also observe the formation of stable bound pairs of spots that move rather fast. We argue that both the rapid motion and the binding itself are due to a pronounced symmetry breaking with respect to size and breakdown phase of the individual spots. Basic features of pairs of spots traveling due to a true two-spot mechanism are discussed.
Brauer
I
Institute of Applied Physics, University of Munster, Corrensstrasse 2/4, D-48149 Munster, Germany.
Bode
M
Ammelt
E
Purwins
H