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Related papers: Polygonal micro-whirlpools induced in ferrofluids

200 papers

Current analytical and numerical modelling suggest the existence of ubiquitous thin current sheets in the corona that could explain the observed heating requirements. On the other hand, new high resolution observations of the corona…

Solar and Stellar Astrophysics · Physics 2015-06-19 P. Antolin , T. Yokoyama , T. Van Doorsselaere

In the presence of a magnetic field applied perpendicular to a thin sample layer, a suspension of magnetic colloidal particles (ferrofluid) can form spatially modulated phases with a characteristic length determined by the competition…

Soft Condensed Matter · Physics 2009-11-07 D. Lacoste , T. C. Lubensky

The surface of both Jupiter and Saturn has magnificent vortical storms which help shape the dynamic nature of their atmospheres. Land- and space-based observational campaigns over time have established several properties of these vortices,…

Earth and Planetary Astrophysics · Physics 2020-11-17 Rakesh Kumar Yadav , Moritz Heimpel , Jeremy Bloxham

We investigate vortex configuration in antiferromagnetic thin discs. It is shown that the vortex acquires oscillatory dynamics with well-defined amplitude and frequency which may be controlled on demand by an alternating spin polarized…

Mesoscale and Nanoscale Physics · Physics 2018-12-19 R. L. Silva , R. C. Silva , R. J. C. Lopes , W. A. Moura-Melo , A. R. Pereira

The design and implementation of a multiplexed spiral phase mask in an experimental optical tweezer setup are presented. This diffractive optical element allows the generation of multiple concentric vortex beams with independent topological…

Linear and non-linear surface waves on a ferrofluid cylinder surrounding a current-carrying wire are investigated. Suppressing the Rayleigh-Plateau instability of the fluid column by the magnetic field of a sufficiently large current in the…

Fluid Dynamics · Physics 2009-11-11 D. Rannacher , A. Engel

This is a brief review of the main results of our recent studies of the nonlinear evolution of the small-scale MHD dynamo in the high-Prandtl-number regime and of the structure of the resulting saturated state of the isotropic homogeneous…

Astrophysics · Physics 2007-05-23 A. A. Schekochihin , S. C. Cowley , G. W. Hammett , J. L. Maron , J. C. McWilliams

We introduce the phenomenon of spiraling vortices in driven-dissipative (non-equilibrium) exciton-polariton condensates excited by a non-resonant pump beam. At suitable low pump intensities, these vortices are shown to spiral along circular…

Quantum Gases · Physics 2020-07-28 Xuekai Ma , Yaroslav V. Kartashov , Tingge Gao , Lluis Torner , Stefan Schumacher

Small angle neutron and x-ray scattering methods are used to investigate the structure of dilute suspensions of two different ferrofluid systems dispersed in soft polyacrylamide hydrogels. It is found that the particles in the fluid are…

We discover the existence of vortex solitons supported by the surface between two optical lattices imprinted in Kerr-type nonlinear media. Such solitons can feature strongly noncanonical profiles, and we found that their properties are…

Structure and properties of two-dimensional spiral textures in helical ferromagnets have been studied. In these magnetic mediums have been predicted new types of periodical structures - spiral lattices.

Strongly Correlated Electrons · Physics 2013-01-03 A. B. Borisov , F. N. Rybakov

A mechanism for constructing single layer valves in microfluidic devices is reported.

Soft Condensed Matter · Physics 2014-06-30 Natalie Arkus

Vortex dynamics in superfluids is investigated in the framework of the nonlinear Schr\"{o}dinger equation. The natural motion of the vortex is of cyclotron type, whose frequency is found to be on the order of phonon velocity divided by the…

Condensed Matter · Physics 2009-10-28 E. Demircan , P. Ao , Q. Niu

Colloidal suspensions of ferromagnetic nano-particles, so-called ferrofluids, are shown to be suitable systems to demonstrate and investigate thermal ratchet behavior: By rectifying thermal fluctuations, angular momentum is transferred to a…

Materials Science · Physics 2009-11-07 Andreas Engel , Hanns Walter Mueller , Peter Reimann , Achim Jung

From a theoretical perspective, we demonstrate that nanometric magnetic skyrmions are created by application of a circularly polarized microwave magnetic field to a thin-plate Dzyaloshinskii-Moriya ferromagnet with fabricated rectangular…

Mesoscale and Nanoscale Physics · Physics 2021-08-31 Masayuki Miyake , Masahito Mochizuki

When a surfactant-stabilised oil droplet with an ultralow interfacial tension is trapped in the focus of two laser beams and pulled apart (by moving the laser beams) a configuration of two droplets connected by a thin tether of oil results.…

Soft Condensed Matter · Physics 2018-01-31 Joshua A. Bull , Alex L. Hargreaves , Colin D. Bain , Buddhapriya Chakrabarti

We report about an intriguing boiling regime occurring for small heaters embedded on the boundary in subcooled water. The microheater is realized by focusing a continuous wave laser beam to about $10\,\mu$m in diameter onto a 165\,nm-thick…

Fluid Dynamics · Physics 2017-02-01 Fenfang Li , Roberto Gonzalez-Avila , Dang Minh Nguyen , Claus-Dieter Ohl

We experimentally generate optical tornado waves using spatial multiplexing on a single-phase modulation device. In their focal region, the intensity pattern outlines a spiral of decreasing radius and pitch. We examine the propagation…

In this paper, we show that equiangular spirals (also known as logarithmic spirals) appear naturally in fluids going through sinks. We provide a simple mathematical model that explains the spiral forms in some natural formations. For this…

History and Overview · Mathematics 2021-10-29 Khristo N. Boyadzhiev

Warped astrophysical discs are usually treated as laminar viscous flows, which have anomalous properties when the disc is nearly Keplerian and the viscosity is small: fast horizontal shearing motions and large torques are generated, which…

Solar and Stellar Astrophysics · Physics 2015-06-15 Gordon I. Ogilvie , Henrik N. Latter