We generate double-charge white-light optical vortices by sending a circularly polarized partially incoherent light through an uniaxial crystal. We show that the generated polichromatic vortices are structurally stable, and their correlation properties can be altered by the beam focusing, resulting in changes of the vortex core visibility.

Linear defects are generic in continuous media. In quantum systems they appear as topological line defects which are associated with a circulating persistent current. In relativistic quantum vacuum they are known as cosmic strings, in superconductors as quantized flux lines, and in superfluids and low-density atomic Bose-Einstein condensates as quantized vortex lines. We discuss unconventional ...

Aims. To determine whether “vortex creep” in neutron stars, the slow motion of neutron vortices with respect to pinning sites in the core or inner crust, is consistent with observations of long-period precession. Methods. Using the concept of vortex drag, I discuss the precession dynamics of a star with imperfectly-pinned (i.e., “creeping”) vortices. Results. The precession frequency is far too...

Aims. To determine whether “vortex creep” in neutron stars, the slow motion of neutron vortices with respect to pinning sites in the core or inner crust, is consistent with observations of long-period precession. Methods. Using the concept of vortex drag, I discuss the precession dynamics of a star with imperfectly-pinned (i.e., “creeping”) vortices. Results. The precession frequency is far too...

Detached Eddy Simulation on a 13 M grid is conducted for a KVLCC2 tanker hull form at drift angle 301. The objective is to identify and analyze the vortical structures, instabilities, and turbulent structures with analogy to the vortex breakdown and helical instability analysis for delta wing at large angles of attack. One shear layer, one Karman-like vortex shedding, and three helical mode ins...

The interaction of two parallel vortices of equal circulation is observed experimentally. For low Reynolds numbers (Re), the vortices remain two-dimensional and merge into a single one, when their time-dependent core size exceeds approximately 30% of the vortex separation distance. At higher Re, a three-dimensional instability is discovered, showing the characteristics of an elliptic instabilit...

The spatial signatures of retrograde spanwise vortices in wall turbulence are assessed from particle-image velocimetry measurements in the streamwise–wall-normal plane of a zero-pressure-gradient turbulent boundary layer at Reτ ≡ u∗δ/ν=2350. The present results suggest that a proportion of retrograde spanwise vortices have a welldefined spatial relationship with neighbouring prograde vortices. ...

It is well-known that a type-II superconductor, while exposed to a magnetic field B whose magnitude is between the lower and upper critical field, is penetrated by a flux-line array of Abrikosov vortices, or fluxons [1–3]. Each vortex contains one magnetic flux quantum, Φ0 = 2.07× 10−15 Wb, and the repulsive interaction between vortices makes them to arrange in a triangular lattice, with the vo...

The structure of multiply quantized or giant vortex states in atomic Fermi gases across a Feshbach resonance is studied within the context of self-consistent Bogoliubov–de Gennes theory. The particle density profile of vortices with 1 flux quanta is calculated. Owing to discrete branches of vortex-core bound states, inside the core the density oscillates as a function of the distance from the v...

The characteristics of the axial flow within the core of a concentrated line vortex are investigated using molecular tagging velocimetry (MTV). A well-defined array of isolated vortices of alternating sign is generated in the wake of a NACA-0012 airfoil pitching sinusoidally at small amplitude and high reduced frequencies. The circulation and peak vorticity of the vortices are varied by the cho...