Formation of the ‘dip’ structure which foregoes switching of magnetic vortex polarity is studied numerically in magnetic nanodisc. A new method based on influence of the spin-transfer torque is used. The method allows one to obtain the dip structure for immobile vortex which significantly improves studying accuracy in comparison with the case of moving vortex. Free out-of-plane vortices as well...

A method is presented whereby the translational velocity of a vortex ring can be approximated from the total circulation, impulse, and kinetic energy of the vortex system. Assuming a uniform vorticity density, these bulk quantities define a unique stable vortex ring configuration, and the translational velocity can be inferred from this configuration and the system scaling. Here, the accuracy o...

In a recent Letter [1], Mun et al. claim to observe vortex glass and lattice melting transitions in superconducting YNi2B2C. A key observation, which they associate with vortex lattice melting, is the presence of a sharp transition in the dc resistivity in finite dc magnetic field. Mun et al. arrive at an HT phase diagram with a single phase boundary which separates the vortex liquid from the v...

This paper is about experimental results for partial reduction of vortex at vertical pipe intakes. One of the easiest and practical ways of reducing vortex effect is to use anti-vortex plates or baffles. These plates can be used to avoid the vortex completely or partially. This paper will concentrate on the latter case. Rectangular plates with different dimensions have been placed at different ...

The existence of vortex condensates in the self-dual Maxwell-ChernSimons-Higgs System on a flat torus is proved by the super-sub solution method under the assumption that the total vortex number in a given periodic domain is not too large. We also study the limiting behaviors of the solutions as the Chern-Simons coupling constant goes to some limits. In the Abelian-Higgs limit we find that our ...

The XY model with quenched random disorder is studied numerically at T 1⁄4 0 by a defect scaling method as a model of a disordered superconductor. In 3D we find that, in the absence of screening, a vortex glass phase exists at low T for large disorder in 3D with stiffness exponent h þ0:31 and with finite screening and in 2D this phase does not exist. For weak disorder, a superconducting phase e...

When a vortex beam with a spiral phase structure passes through dynamic angular double slits (ADS), the interference pattern changes alternatively between destructive and constructive at the angular bisector of the ADS. This change is due to their phase difference. Based on this property, we experimentally demonstrate a simple method to precisely and efficiently determine the topological charge...

A new method for directly assimilating Lagrangian tracer observations for flow state estimation is presented. It is developed in the context of point vortex systems. With tracer advection equations augmenting the point vortex model, the correlations between the vortex and tracer positions allow one to use the observed tracer positions to update the non-observed vortex positions. The method work...

We study the growth of disturbances to vortex rings with swirl, which are exact solutions of the Euler equations of inviscid ow, using two contrasting methods. The motion of the perturbed vortex rings can be regarded as a prototype for the inviscid dynamics of vortex structures in 3D. Exact rings with swirl are computed as steady, axisymmetric ows using a variational method. Asymptotic analysis...

In this investigation we propose a computational approach for solution of optimal control problems for vortex systems with compactly supported vorticity. The problem is formulated as PDE–constrained optimization in which the solutions are found using a gradient–based descent method. Recognizing such Euler flows as free– boundary problems, the proposed approach relies on shape differentiation co...