Charge Flipping Vortices in DNLS trimer and hexamer
2015 (English)In: PHOTONICA 2015. V International School and Conference on Photonics& COST actions: MP1204 and BM1205 & the Second international workshop "Control of light and matter waves propagation and localization in photonic lattices“, Belgrad 2015: Book of Abstracts / [ed] Suzana Petrović , Goran Gligorić and Milutin Stepić, Belgrade, Serbia: Vinča Institute of Nuclear Sciences , 2015, 65-65 p.Conference paper, Poster (Other academic)
We examine the existence and properties of Charge Flipping Vortices (CFVs), rtices which periodically flip the topological charge, in three-site (trimer) and six-site (hexamer) discrete nonlinear Schrödinger (DNLS) lattices. We demonstrate numerically that CFVs exist as exact quasiperiodic solutions in continuous families which connect two different stationary solutions without topological charge, and that it is possible to interpret the dynamics of certain CFVs as the result of perturbations of these stationary solutions. The CFVs are calculated with high numerical accuracy and we may therefore accurately determine many of their properties, such as their energy and linear stability, and the CFVs are found to be stable over large parameter regimes.
We also show that, like in earlier studies for lattices with a multiple of four sites, trimer and hexamer CFVs can be obtained by perturbing stationary constant amplitude vortices with certain linear eigenmodes. However, in contrast to the former case where the perturbation could be infinitesimal, the magnitude of the perturbations for trimers and hexamers must overcome a quite large threshold value. These CFVs may be interpreted as exact quasiperiodic CFVs, with a small perturbation applied to. The concept of a charge flipping energy barrier is introduced and discussed.
P. Jason, M. Johansson, Phys. Rev. E. 91, 022910 (2015).
Place, publisher, year, edition, pages
Belgrade, Serbia: Vinča Institute of Nuclear Sciences , 2015. 65-65 p.
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:liu:diva-123929ISBN: 978-86-7306-131-3OAI: oai:DiVA.org:liu-123929DiVA: diva2:893974
5th International School and Conference on Photonics - PHOTONICA2015, Belgrade, Serbia, August 24 - 28, 2015