We report on low temperature scanning tunneling microscopy (STM) studies of the electronic structure of vortex cores in Bi2Sr2CaCu2O81d. At the vortex core center, an enhanced density of states is observed at energies near V 67 meV. Spectroscopic imaging at these energies reveals an exponential decay of these “core states” with a decay length of 22 6 3 Å. The fourfold symmetry sometimes predict...

This project was focused on a basic scientific problem, one that is at the heart of application and development of superconductivity for efficient energy usage. This is improvement in high current density which can only be achieved by learning to pin vortices to the physical structure of its underlying superconducting material. Quantized vortices are the tornado of electrical supercurrents, ubi...

2014 In this paper we review the theoretical problems due to the pinning of vortices. We emphasize the difficulty of making a link between the elementary pinning force between an isolated vortex and a pinning center with the measured pinning force. We show how to define experimentally the pinning force which permit a theoretical study and we calculate it. Far from Hc2, we get Webb’s results. Fi...

We have observed and characterized the dynamics of singly quantized vortices in dilute-gas Bose-Einstein condensates. Our condensates are produced in a superposition of two internal states of 87Rb, with one state supporting a vortex and the other filling the vortex core. Subsequently, the state filling the core can be partially or completely removed, reducing the radius of the core by as much a...

Dense Medium Cyclone is a high capacity device that is widely used in coal preparation. It is simple in design but the swirling turbulent flow, the presence of medium and coal with different density and size fraction and the presence of the air-core make the flow pattern in DMCs complex. In this article the flow pattern simulation of DMC is performed with computational fluid dynamics and Fluent...

We use an autonomous three-dimensional dynamical system to study embedded vortex structures that are observed to form in computational fluid dynamic simulations of patient-specific cerebral aneurysm geometries. These structures, described by a vortex which is enclosed within a larger vortex flowing in the opposite direction, are created and destroyed in phase space as fixed points undergo saddl...

The N-vortex solutions to the two-dimensional Ginzburg-Landau equations for the κ = 1/ √ 2 parameter are built. The exact solutions are derived for the vortices with large numbers of the magnetic flux quanta. The size of vortex core is supposed to be much greater than the magnetic field penetration depth. In this limiting case the problem is reduced to the determination of vortex core shape. Th...