Two-dimensional Lagrangian trajectories of the inertial particle in helium II are analyzed in the vicinity of the triple vortex structure (i.e. the superfluid vortex and the normal dipole-like vortex structure induced by the mutual friction). It is shown that the vortices in the normal fluid can deflect the particle which otherwise would have collided with the superfluid vortex and, provided th...

Here the hollow vortex Gaussian beam is described by the exact solution of the Maxwell equations. By means of the method of the vectorial angular spectrum, analytical expressions of the electromagnetic fields of a hollow vortex Gaussian beam propagating in free space are derived. By using the electromagnetic fields of a hollow vortex Gaussian beam beyond the paraxial approximation, one can calc...

Vortex structures in soft magnetic nanodisks are highly attractive due to their scientific beauty and potential technological applications. Here, we experimentally demonstrated the resonant amplification of vortex oscillations by application of simple coherent field pulses tuned to optimal width and time intervals. In order to investigate vortex excitations on the sub-ns time scale, we employed...

The interaction of gas bubbles with a vortex is investigated experimentally to clarify the role of the initial bubble position on its trajectory around the tip vortex shed from a large hydrofoil. The experiments performed with 4-6mm bubbles show that the bubbles can undergo no capture, quick capture into the tip vortex or slow capture with a spiral trajectory around the vortex.

We reveal that spatially localized vortex solitons become stable in self-focusing nonlinear media when the vortex symmetry-breaking azimuthal instability is eliminated by a nonlocal nonlinear response. We study the main properties of different types of vortex beams and discuss the physical mechanism of the vortex stabilization in spatially nonlocal nonlinear media.

The two-dimensional ~2-D! merging of an intense, pointlike vortex with a diffuse, extended vortex is investigated with experiments using strongly magnetized electron columns in a Malmberg– Penning trap, and with numerical simulations using a 2-D particle-in-cell code. The study is restricted to highly nonlinear conditions, where the perturbative approach does not apply. A very good agreement be...

We discuss the elementary vortex pinning in type-II superconductors in connection with the Anderson’s theorem for nonmagnetic impurities. We address the following two issues. One is an enhancement of the vortex pinning energy in the unconventional superconductors. This enhancement comes from the pair-breaking effect of a nonmagnetic defect as the pinning center far away from the vortex core (i....

Amagnetic nanoparticle in a vortex state is a promising candidate for the information storage. One bit of information corresponds to the upward or downward magnetization of the vortex core (vortex polarity). The dynamics of the magnetic vortex driven by a spin current is studied theoretically. Using a simple analytical model and numerical simulations, we show that a nondecaying vortex motion ca...

In this study the augmentation of heat transfer in a rectangular channel with triangular vortex generators is evaluated. The span wise averaged Nusselt number, mean temperature and total heat flux are compared with and without vortex generators in the channel at a blade angle of 30° for Reynolds numbers 800, 1200, 1600, and 2000. The use of vortex generators increases the span wise averaged Nus...

This article reviews some recent simulations of vortex sheet roll-up using the vortex blob method. In planar and axisymmetric flow, the roll-up is initially smooth but irregular small-scale features develop later in time due to the onset of chaos. A numerically generated Poincaré section shows that the vortex sheet flow resembles a chaotic Hamiltonian system with resonance bands and a heterocli...