title: Radial sine-Gordon kinks as sources of fast breathers.
abstract: We consider radial sine-Gordon kinks in two, three, and higher dimensions. A full two-dimensional simulation showing that azimuthal perturbations remain small allows us to reduce the problem to the one-dimensional radial sine-Gordon equation. We solve this equation on an interval [r(0),r(1)] and absorb all outgoing radiation. As the kink shrinks toward r(0), before the collision, its motion is well described by a simple law derived from the conservation of energy. In two dimensions for r(0)≤2, the collision disintegrates the kink into a fast breather, while for r(0)≥4 we obtain a kink-breather metastable state where breathers are shed at each kink "return." In three and higher dimensions d, an additional kink-oscillon state appears for small r(0). On the application side, the kink disintegration opens the way for new types of terahertz microwave generators.
authors.affiliation: Department of Mathematics, University of Arizona, Tucson, Arizona 85719, USA.
authors.forename: J-G
authors.initials: JG
authors.lastname: Caputo
authors.forename: M P
authors.initials: MP
authors.lastname: Soerensen