Zobrazeno 1 - 10
of 153
pro vyhledávání: '"Komineas, S."'
Autor:
Komineas, S., Roy, P. E.
Breathing oscillations of skyrmions in chiral antiferromagnets can be excited by a temporal modification of the Dzyaloshinskii-Moriya interaction or magnetocrystalline anisotropy strength. We employ an adiabatic approximation and derive a formula for
Externí odkaz:
http://arxiv.org/abs/2203.04157
Autor:
Komineas, S., Papanicolaou, N.
Publikováno v:
J. Math. Phys. 51, 042705 (2010)
The dynamics of N point vortices in a fluid is described by the Helmholtz-Kirchhoff (HK) equations which lead to a completely integrable Hamiltonian system for N=2 or 3 but chaotic dynamics for N>3. Here we consider a generalization of the HK equatio
Externí odkaz:
http://arxiv.org/abs/0911.2377
Publikováno v:
Physical Review E 79, 056211 (2009)
We consider the spatiotemporal evolution of a wave packet in disordered nonlinear Schr\"odinger and anharmonic oscillator chains. In the absence of nonlinearity all eigenstates are spatially localized with an upper bound on the localization length (A
Externí odkaz:
http://arxiv.org/abs/0901.4418
Publikováno v:
Phys. Rev. Lett. 100, 084103 (2008)
We study the spreading of an initially localized wavepacket in two nonlinear chains (discrete nonlinear Schroedinger and quartic Klein-Gordon) with disorder. Previous studies suggest that there are many initial conditions such that the second moment
Externí odkaz:
http://arxiv.org/abs/0710.2621
Autor:
Komineas, S.
Publikováno v:
Phys. Rev. Lett. 99, 117202 (2007)
Vortex-antivortex pairs are localized excitations and have been found to be spontaneously created in magnetic elements. In the case that the vortex and the antivortex have opposite polarities the pair has a nonzero topological charge, and it behaves
Externí odkaz:
http://arxiv.org/abs/0705.2977
Autor:
Komineas, S., Cooper, N. R.
Publikováno v:
Phys. Rev. A 75, 023623 (2007)
We study the ground states of rotating atomic Bose-Einstein condensates with dipolar interactions. We present the results of numerical studies on a periodic geometry which show vortex lattice ground states of various symmetries: triangular and square
Externí odkaz:
http://arxiv.org/abs/cond-mat/0610702
Publikováno v:
Phys. Rev. A 72, 053624 (2005)
It has been demonstrated experimentally that non-axially symmetric vortices precess around the centre of a Bose-Einstein condensate. Two types of single vortex states have been observed, usually referred to as the S-vortex and the U-vortex. We study
Externí odkaz:
http://arxiv.org/abs/cond-mat/0508562
Publikováno v:
Phys. Rev. A 72, 053609 (2005)
We derive a class of virial theorems which provide stringent tests of both analytical and numerical calculations of vortex states in a confined Bose-Einstein condensate. In the special case of harmonic confinement we arrive at the somewhat surprising
Externí odkaz:
http://arxiv.org/abs/cond-mat/0508563
Publikováno v:
Phys. Rev. B 71, 060405(R) (2005)
We study the fundamental magnetic states of disc-shaped ferromagnetic particles with a uniaxial anisotropy along the symmetry axis. Besides the monodomain, a bidomain state is also identified and studied both numerically and theoretically. This bidom
Externí odkaz:
http://arxiv.org/abs/cond-mat/0409129
Publikováno v:
Phys. Rev. A 70, 033604 (2004)
We present the results of numerical calculations of the groundstates of weakly-interacting Bose-Einstein condensates containing large numbers of vortices. Our calculations show that these groundstates appear to be close to uniform triangular vortex l
Externí odkaz:
http://arxiv.org/abs/cond-mat/0404112