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Optical modes allow for the transmission of data by propagating light in a singular coherent form along the channel. By constructing a special waveguide structure, a unique mode may be formed in a plane perpendicular to the transmission axis. This paper elucidates on the design of a waveguide to generate unique vortex modes and analyses the properties of the generated modes. [ABSTRACT FROM AUTHOR]

Non-incidence flow rate determination is necessary in the calculation of gas-dynamic characteristics of a centrifugal compressor by the Universal Modeling Method, since the magnitude of incidence losses depends on this. The direction of the critical streamline is affected by the decrease in the flow area by the blades of finite thickness and the load of the blades. In the course of primary design, the Universal Modeling Method uses a scheme of replacing the influence of the blade load with the effect of a vortex with identical circulation. Finally, the value of the inlet blade angle is selected by calculating the inviscid flow around the blades. For impellers with small design flow coefficients, the condition of the non-incidence inlet for the primary design and for the calculation of the inviscid flow is significantly different. The correctness of the calculation of the non-incidence regime for non-viscous flow was checked earlier by measurements of the flow in the impellers. CFD calculations and no-viscid calculations of twenty impellers were made in a tenfold range of design flow coefficients. The identity of inlet conditions by both methods was shown. To increase the accuracy of the primary design, the calculation model was refined. An empirical coefficient is introduced into the formula for calculating the velocity induced by the vortex. The analysis of data for 32 impellers with different blade profiling allowed to propose out formulae for calculating empirical coefficient, depending on the type of impeller, the blade load and the width of the throat at an impeller inlet. The calculation based on the new scheme with the empirical coefficient is accurate enough for the primary design. [ABSTRACT FROM AUTHOR]

Vortex reconnections plays an important role in the turbulent flows associated with the superfluids. To understand the dynamics, we examine the reconnections of vortex rings in the superfluids of dilute atomic gases confined in trapping potentials using Gross-Petaevskii equation. Further more we study the reconnection dynamics of coreless vortex rings, where one of the species can act as a tracer. [ABSTRACT FROM AUTHOR]

The distribution of electrical potential and electron density near foil, resulting to vortical electron dynamics at interaction of an intensive laser pulse with a foil, is considered. [ABSTRACT FROM AUTHOR]

Microgravity separation is a critical need for the development of high performance thermal management and advanced life support systems. Texas A&M has been working in the area of vortex separation for several years (Carron and Best, 1991; Kurwitz and Best, 2000). Recent reduced gravity flight data has been analyzed to compare the interface position and shape as a function of liquid inventory and rotational speed. A comparison of the measured interface location with the interface shape predicted from irrotational flow resulted in a RMSD of 0.45 cm and the RMSD of the measured interface location to an interface determined assuming that the gas forms a right circular cylinder centrally located in the separator was 0.7015. The accuracy of the prediction method is better at higher rotational speeds corresponding to larger flow rates. The high degree of fidelity between the measured interface location with that predicted using a simple irrotational flow assumption indicates that secondary flows are small in magnitude compared to the rotational flow of liquid and provides a high degree of confidence in the prediction of reduced gravity performance. [ABSTRACT FROM AUTHOR]

Symmetry broken electronic states give rise to topological defects: from extended domain walls—“stripes” as solitonic lattices to microscopic solitons as anomalous quasi-particles and instantons in their dynamics. We shall collect and interpret experimental evidences on existence of microscopic solitons, and their determining role in electronic processes of quasi-1D electronic crystals. Thus, the ferroelectric charge ordering in organic conductors gives access to several types of solitons observed in conductivity (holons) and in permittivity (polar kinks), to solitons’ bound pairs in optics, to compound charge-spin solitons. In charge density waves, the individual phase solitons have been visually captured in recent STM experiments. The resolved subgap tunneling spectra recover these solitons (in aggregated form of dislocations in statics and as instantons—the phase slips in dynamics), as well as the amplitude kinks—the spinons. The theory relies upon the regime of quantum dissipation provided by soft mode emittance in the course of the soliton creation, and on effects of dimensional crossover. With onset of a 2D or a 3D long range order, the topologically nontrivial solitons experience the confinement resulting in the spin-charge recombination. It originates the symmetry broken spin-or charge- roton configurations with charge- or spin- kinks localized in the core, correspondingly for cases of repulsion and attraction. These complex excitations can be viewed as nucleuses of the melted stripe phases, which appears in doped antiferromagnetic—Mott insulators or in spin-polarized superconductors and charge density waves. [ABSTRACT FROM AUTHOR]

The inner crust of a neutron star is expected to contain a Coulomb lattice of nuclei immersed in a superfluid sea of free neutrons. The rotation of the star induces the formation of vortices in the neutron sea, whose dynamics is influenced by the interaction with the nuclei. In particular, this interaction is important to determine whether it is energetically advantageous for vortices to pin on nuclei or not. We find that the pinning energy is sensitive to quantal size effects. In fact, the nuclear shell structure tends to hinder the formation of vortices inside the nuclear volume. [ABSTRACT FROM AUTHOR]

The growing body of anomalies in new energy, low energy nuclear reactions, astrophysics, atomic physics, and entanglement, combined with the failure of the Standard Model and string theory to predict many of the most basic fundamental phenomena, all point to a need for major new paradigms. Not Band-Aids, but revolutionary new ways of conceptualizing physics, in the spirit of Thomas Kuhn’s The Structure of Scientific Revolutions. This paper identifies a number of long-held, but unproven assumptions currently being challenged by an increasing number of alternative scientists. Two common themes, both with venerable histories, keep recurring in the many alternative theories being proposed: (1) Mach’s Principle, and (2) toroidal, vortex particles. Matter-based Mach’s Principle differs from both space-based universal frames and observer-based Einsteinian relativity. Toroidal particles, in addition to explaining electron spin and the fundamental constants, satisfy the basic requirement of Gauss’s misunderstood B Law, that motion itself circulates. Though a comprehensive theory is beyond the scope of this paper, it will suggest alternatives to the long list of assumptions in context. [ABSTRACT FROM AUTHOR]

Even though the static properties of quantum systems have been known since the early days of quantum mechanics, accurate simulation of the dynamical break-up or ionization remains a theoretical challenge despite our complete knowledge of the relevant interactions. Simulations are challenging because of highly oscillatory exponential phase factors in the electronic wave function and the infinitesimally small values of the continuum components of electronic probability density at large times after the collision. The approach we recently developed, the regularized time-dependent Schrödinger equation method, has addressed these difficulties by removing the diverging phase factors and transforming the time-dependent Schrödinger equation to an expanding space. The evolution of the electronic wave function was followed to internuclear distances of R = 100,000 a.u. or 5 microns, which is of the order of the diameter of a human hair. Our calculations also revealed unexpected presence of free vortices in the electronic wave function. The discovered vortices also bring new light on the mechanism of transferring of the angular momentum from an external to internal motion. The connection between the observable momentum distribution and the time-dependent wave function implies that vortices in the wave function at large times are imaged in the momentum distribution. [ABSTRACT FROM AUTHOR]

Recently, it has been observed that there exists a class of vortices which rotates in the opposite direction to E×B drift (referred to as anti-E×B vortex). This result suggests that a predominant force other than electric field is acting on ions. It is found that momentum transport and resultant force generation through the interaction between ions and neutral flow play an essential role on anti-E×B vortex formation. The existence of inward neutral flow, which drives the ions in the anti-E×B direction, has been confirmed using a newly-developed high-resolution laser induced fluorescence (LIF) spectroscopy system. [ABSTRACT FROM AUTHOR]

The Single Transverse — Spin Asymmetry (SSA) is analysed in the framework of the Strongly Correlated Quark Model proposed by author, where the proton spin emerges from the orbital momenta of quark and qluon condensates circulating around the valence quarks. It is shown that dominating factors of appearance of SSA are the orbiting around the valence quarks sea quark and qluon condensates and spin dependent quark-quark cross sections. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A gaseous Bose-Einstein condensate (BEC) offers an ideal testing ground for studying symmetry breaking, because a trapped BEC system is in a mesoscopic regime, and situations exist under which symmetry breaking may or may not occur. Investigating this problem can explain why mean-field theories have been so successful in elucidating gaseous BEC systems and when many-body effects play a significant role. We substantiate these ideas in four distinct situations: namely, soliton formation in attractive BECs, vortex nucleation in rotating BECs, spontaneous magnetization in spinor BECs, and spin texture formation in dipolar BECs. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Vortex dynamics in 3He-B is divided by the temperature dependent damping into a high-temperature regime, where the number of vortices is conserved, and a low-temperature regime, where rapid vortex multiplication takes place in a turbulent burst. We investigate experimentally the hydrodynamic transition between these two regimes by injecting seed vortex loops into vortex-free rotating flow. The onset temperature of turbulence is dominated by the roughly exponential temperature dependence of vortex friction, but its exact value is found to depend on the injection method. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We report highly sensitive specific heat measurements on mesoscopic superconducting loops at low temperature. These mesoscopic systems exhibit thermal properties significantly different from that of the bulk materials. The measurement is performed on a silicon membrane sensor where 450 000 superconducting aluminium loops are deposited through electron beam lithography, under an applied magnetic field. Each entry of a vortex is associated to a jump in the specific heat of few thousands of Boltzmann constant kB indicating the existence of phase transitions. The periodicity of this sequential phase transitions is a nontrivial behaviour and varies strongly as the temperature is decreased. The successive phase transitions are well described by the Ginzburg-Landau theory of superconductivity. The presence of metastable states is responsible for the n[uppercase_phi_synonym]0 (n=1, 2, 3...) periodicity of the discontinuities of the measured specific heat. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The new exact solution of gas dynamics equation, called Ovsyannikov vortex, is investigated. It is the generalization of radial symmetrical solutions. These solutions describe gas source with nonzero curl. The applications for simulation of hurricanes are discussed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

I give a summary of Section E of the sixth edition of the Conference Quark confinement and the hadron spectrum. Papers were presented on different subjects, from spectroscopy, including pentaquarks and hadron structure, to new physics effects (non commutative field theories, supersymmetry and extra dimensions) and the problem of color confinement, both in ordinary Yang-Mills models and in supersymmetric Yang-Mills. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this talk, we review some recent results of the center vortex model for the infrared sector of SU(3) Yang-Mills theory. Particular emphasis is put on the order of the finite-temperature deconfining phase transition and the geometrical structure of vortex branchings. We also present preliminary data for the ’t Hooft loop operator and the dual string tension near the phase transition. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

I review free and trapped Bose-Einstein condensates (BECs) [1, 2, 3, 4, 5]. In an isotropic harmonic potential V(r) = 1/2Mω2r2, the single-particle ground state introduces a new intrinsic scale of length [the ground-state size d = h/(Mω)] and energy [the ground-state energy E0 = 3/2hω]. When the trap rotates [6, 7, 8], there is a critical angular velocity for the appearance of one or a few quantized vortices. For more rapid rotation [9, 10, 11, 12, 13] the condensate contains a vortex array. The resulting centrifugal forces expand the condensate radially and shrink it axially; thus the condensate becomes effectively two-dimensional. If the external rotation speed approaches the frequency of the radial harmonic confining potential, the condensate enters the “lowest-Landau-level” regime, and a simple description again becomes possible [14, 15]. Eventually, the system is predicted to make a quantum phase transition to a highly correlated state analogous to the fractional quantum Hall states of electrons in a strong magnetic field [16, 17, 18, 19, 20]. [ABSTRACT FROM AUTHOR]

We investigate numerically stable structures of vortex states in rotating two-component Bose-Einstein condensates (BECs) in a quadratic plus quartic potential. We discover various new vortex structures by changing the intracomponent coupling constants, the intercomponent coupling constant and the rotation frequency. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have measured NMR spectra of the 3He-A phase restricted between parallel plates under rotation at a speed of Ω < 6.28 rad/s, using a rotating cryostat at ISSP. The sample volume was divided by the plates into 110 disk-shaped spaces, each with a thickness of 12.5 μm and a radius of 1.5 mm. They were connected to a bulk superfluid through 0.3 mm-wide channels. Measurements were done by continuous wave (cw) NMR at 869 kHz. The axes of both H and Ω were perpendicular to the parallel plates. We observed a very narrow spectrum with a negative frequency shift, an indication that the gaps and the superfluid texture were well designed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present here a simple model to examine the effect of oscillating superfluid velocity on a quantized vortex. This situation can be realized in vibrating wire or vibrating grid experiments where the vortices are attached to the oscillating wires. Within this model we determine the critical velocity, above which the vortex motion becomes irregular and new vortices are created. We also determine the vortex creation rates. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The paring sysmmetry of the triplet superconductor Sr2RuO4 is still controversial. Recently, the scanning tunneling microscopy measurement has been done on the quasi-particle structure in Sr2RuO4. They obtained the local density of states around a single vortex. Using the Bogoliubov-de Gennes equation in the differential form off-wave (Δ± (k) = Δd (kx ± ky) cos (ckz)) superconductivity that has the horizontal nodes, we investigate the quasi-particle structure. As compared with the p-wave pairing, the local density of states of f-wave paring at the vortex core is much similar to the experimental data. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Layered organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br shows a step-like softening in the sound velocity below the superconducting transition temperature. In this study, we have measured the sound velocity in the superconducting state of κ-(BEDT-TTF)2Cu[N(CN)2]Br in the applied magnetic field for various directions. The sound velocity as a function of the applied magnetic field shows remarkable elastic anomalies around H = 2 T. It was found that, the magnetic field parallel to the conducting planes of κ-(BEDT-TTF)2Cu[N(CN)2]Br, the sound velocity shows a sharp peak, which is considered to be related to the pinning by Josephson vortices. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Vortex lattice compression moduli in ceramic YBaCuO are studied by measurement of ac response U in the hollow of a cylinder existing in the mixed state. Investigations were performed at stationary magnetic fields H up to 1200 Oe, when the elastic moduli have a non-local character resulting in saturation of the U(H) dependence at large values of H. The analysis of the frequency dependence of the studied response permits to conclude that the wave-vector of vortex lattice deformation decreases with increase of excitation frequency. The penetration of the signal into the hollow increases at reduction of the frequency down to values about 5 kHz; at the further frequency reduction abrupt strengthening of the signal screening is observed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The problem of a vortex electromagnetic mass in a superconductor is considered accounting for the self-interaction effect conditioned by the coupling of the moving vortex to the excited fluctuations of the superfluid density. In the framework of the phenomenological model used, the self-interaction is defined as an interaction of the singular phase with the induced polarization of the charged superfluid. The obtained polaron-type mass exceeds the earlier obtained electromagnetic mass in view of the large value of the light speed relation to the Fermi velocity c/vF, and can dominate over the vortex core mass. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Two-dimensional vortex dynamics in a ratchet planar pinning potential (PPP) in the presence of thermal fluctuations is considered on the basis of a Fokker-Planck equation. Explicit expressions for two new nonlinear anisotropic voltages (longitudinal and transverse with respect to the current direction) are derived and analyzed. The physical origin of these odd (with respect to magnetic field or transport current direction reversal) voltages is caused by the interplay between the even effect of vortex guiding and the ratchet asymmetry. Both new voltages are going to zero in the linear regimes of the vortex motion (i.e. in the thermoactivated flux flow (TAFF) and ohmic flux flow (FF) regimes) and have a bump-like current or temperature dependence in the vicinity of the highly nonlinear resistive transition from TAFF to FF. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]