We present a method for numerically building a vortex knot state in the superfluid wave function of a Bose-Einstein condensate. We integrate in time the governing Gross-Pitaevskii equation to determine evolution and shape preservation of the two (topologically) simplest vortex knots which can be wrapped over a torus. We find that the velocity of a vortex knot depends on the ratio of poloidal an...

We study the spin and vortex dynamics in the spontaneous vortex phase of magnetic superconductors. Equations of motion are derived which incorporate the coupling between the superconducting and magnetic components, as well as coupling between spin and vortex motion. We show that coupling between the spin and vortex degrees of freedom leads to new dynamical phenomena in the spontaneous vortex ph...

We study interaction of a discrete vortex with a supporting photonic lattice and analyze how the combined action of the lattice periodicity and the medium nonlinearity can modify the vortex structure. In particular, we describe theoretically and observe in experiment, for the first time to our knowledge, the nontrivial topological transformations of the discrete vortex including the flipping of...

this paper presents numerical calculations for podded propulsion system using vortex theory and potential panel method. the method discretizes the surface boundary of the body (propeller +pod+strut) and obtained the vortex and propeller surface and potential on strut and pod. a model propeller and strut are considered for these calculations and the results of pressure distribution, flow field a...

We propose a phenomenological equation for the vortex line density in rotating BoseEinstein condensates as a function of the angular speed. This equation provides a simple description of the gross features of the increase in vortex number from the appearance of the first vortex to the theoretical rigid-body result for high vortex density, and allows one to compare with analogous situations in s...

We found the equilibrium conditions for a self-gravitating toroidal vortex by taking thermal pressure into account. These conditions are shown to significantly differ from those for a disk or a sphere. The evolution of a thin vortex turns it into a compact vortex that loses mechanical stability for low masses at a polytropic index γ < 4/3 but retains stability for sufficiently high masses and d...

The influence of disorder on the transport of quantum vortices in one-dimensional arrays of Josephson junctions was studied experimentally. The vortices localize in disordered arrays for small vortex densities resulting in a vanishing transport at low temperatures, whereas, in a periodic array, transport remains possible. For large vortex densities the mobility of vortices is maintained in the ...

The motion of vortices in an anisotropic superconductor is considered. For a system of well-separated vortices, each vortex is found to obey a law of motion analogous to the local induction approximation, in which velocity of the vortex depends upon the local curvature and orientation. A system of closely packed vortices is then considered, and a mean field model is formulated in which the indi...

In this paper, the mechanism of momentum deficit formation about the vortex legs is deeply studied. A new mechanism on how the multiple rings are formed one by one is presented. It is found that the momentum deficit is generated by vortex ring leg ejection. The momentum deficit forms shear layers above the vortex legs. The shear layers finally form new vortex rings one by one.

In superfluid He-A singly and doubly quantized vortex lines can coexist in a rotating container. We measure with NMR techniques the radial distribution of the two vortex types in an array of vortex lines. The radial composition is found to depend on the procedure by which the array has been formed. The result shows that in superfluid He the energy barriers separating different configurations of...