In this paper, we show that improved air circulation above a heat sink is possible using thin winglet-type vortex generators that can be passively retrofitted to an existing unit. By mounting these vortex generators on the leading edge of heat sink fins, pairs of counterrotating vortices are induced within the interfin spacing. The vortices disturb the boundary layers and serve to mix the air i...

Scanning μSQUID force microscopy is used to study magnetic flux structures in single crystals of the layered spin triplet superconductor Sr2RuO4. Images of the magnetic flux configuration above the ~a~b-face of the cleaved crystal are acquired, mostly after field-cooling the sample. For low applied magnetic fields, individual vortices are observed, each carrying a single quantum of flux. Above ...

In this paper we compare experimentally two methods of detecting optical vortices from Shack-Hartmann wavefront sensor (SHWFS) data, the vortex potential and the contour sum methods. The experimental setup uses a spatial light modulator (SLM) to generate turbulent fields with vortices. In the experiment, many fields are generated and detected by a SHWFS, and data is analysed by the two vortex d...

We examine the spectrum of small perturbations around global and local (gauge) abelian vortices, using simple numerical matrix techniques. The results are of interest both for cosmic strings and for their condensed matter analogues, superfluid and superconductor vortices. We tabulate the instabilities of higher winding number vortices, and find several bound states. These localised coherent osc...

In this paper we predict many interesting new properties of vortices in highly anisotropic density wave systems subject to strong transverse electric fields. We mainly concentrate on ground state properties. Besides electric field-induced vortices we consider also thermally activated vortices. A new type of temperature-driven transition between two different phases of density waves in strong fi...

We study the propagation of off-axis vortices in a paraxial beam formed by two collinear Laguerre-Gauss beams. We show that the vortices move about the beam axis as the light propagates resulting in a rotation of the beam's transverse profile. This rotation is explained by the Gouy phase acquired by the component beams. Experimental measurements of the angular position of the vortices are in go...

We calculate the overlap between two many-body wave functions for a superfluid film containing a vortex at shifted positions. Comparing the results to phenomenological theories, which treat vortices as point particles, we find that the results are consistent if the point-particle vortices are considered as under the action of the Magnus force and in weak interaction with sound waves of the supe...