2,601 research outputs found
Persistent spin currents in an elastic Landau system
We consider a neutral particle with permanent magnetic dipole moment in an
elastic medium with the presence of a uniform distribution of screw
dislocations interacting with a radial electric field. We show that the uniform
distribution of dislocations plays the role of an effective uniform magnetic
field, and obtain a spectrum of energy which depends on the Aharonov-Casher
geometric phase [Y. Aharonov and A. Casher, Phys. Rev. Lett. 53, 319 (1984)].
Moreover, from the dependence of energy levels on the Aharonov-Casher geometric
phase, we calculate the persistent spin currents in this elastic Landau system
Eliminating spurious velocities in the free energy lattice Boltzmann method
Spurious velocities are unphysical currents that appear close to curved
interfaces in diffuse interface methods. We analyse the causes of these
spurious velocities in the free energy lattice Boltzmann algorithm. By making a
suitable choice of the equilibrium distribution, and by finding the best way to
numerically calculate derivatives, we show that these velocities may be
decreased by an order of magnitude compared to previous models. Furthermore, we
propose a momentum conserving forcing method that reduces spurious velocities
by another factor of ~5. In three dimensions we find that 19 velocity vectors
is the minimum number necessary.Comment: 8 pages, 3 figure
Lorentz symmetry breaking effects on relativistic EPR correlations
Lorentz symmetry breaking effects on relativistic EPR
(Einstein-Podolsky-Rosen) correlations are discussed. From the modified Maxwell
theory coupled to gravity, we establish a possible scenario of the Lorentz
symmetry violation and write an effective metric for the Minkowski spacetime.
Then, we obtain the Wigner rotation angle via the Fermi-Walker transport of
spinors and consider the WKB ((Wentzel-Kramers-Brillouin) approximation in
order to study the influence of Lorentz symmetry breaking effects on the
relativistic EPR correlations.Comment: Accepted for publication in The European Physical Journal C. arXiv
admin note: substantial text overlap with arXiv:1504.07432, arXiv:1504.07262,
arXiv:1412.5080, arXiv:1506.0056
Bound states in the dynamics of a dipole in the presence of a conical defect
In this work we investigate the quantum dynamics of an electric dipole in a
-dimensional conical spacetime. For specific conditions, the
Schr\"odinger equation is solved and bound states are found with the energy
spectrum and eigenfunctions determined. We find that the bound states spectrum
extends from minus infinity to zero with a point of accumulation at zero. This
unphysical result is fixed when a finite radius for the defect is introduced.Comment: 4 page
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