Q-ring


Metastable ringlike semitopological solitons


M. Axenides a, E. Floratosa S. Komineasb, L. Perivolaropoulosa,
aInstitute of Nuclear Research, N.C.R.P.S. Demokritos, 15310 Athens, Greece
bPhysikalisches Institut, Universitat Bayreuth D-95440 Bayreuth, Germany






Abstract

We show the existence of new stable ring-like localized scalar field configurations whose stability is due to a combination of topological and nontopological charges. In that sense these defects may be called semitopological. These rings are Noether charged and also carry Noether current (they are superconducting). They involve a single complex scalar field and they appear in theories where a U(1) symmetry remains unbroken. We obtain numerical solutions of the field configuration corresponding to large rings and derive virial theorems demonstrating their stability. We also derive the minimum energy field configurations in 3D and simulate the evolution of a finite size Q ring on a three dimensional lattice thus generalizing our demonstration of stability.