Related papers: Calculation of levitation forces in permanent-supe…
The current density in a disk-shaped superconducting bulk magnet and the magnetic levitation force exerted on the superconducting bulk magnet by a cylindrical permanent magnet are calculated from first principles. The effect of the…
The levitation forces between a permanent magnet and a coaxial superconducting disk after different magnetization processes are measured. Significant effect of the magnetization process on the levitation force is observed. Theoretical…
The distribution of the current density and the profile of the trapped magnetic field of a superconducting disk magnetized by uniform field are calculated from first principles. The effect of the superconducting parameters is taken into…
The distributions of the magnetic field and temperature in a superconducting-disk magnetized by pulse field, and the levitation force between this disk and a permanent magnet are calculated from first principles. The calculation is based…
The flux creep problem for a superconductor slab placed in a constant or time-dependent magnetic field is considered. Logarithmic dependence of the activation energy on the current density is assumed, U=U0 ln(J/Jc), with a field dependent…
The dependence of the magnetic field strength required for levitation of a melt textured, single domain YBCO superconductor disc on the frequency of the current generating the levitating magnetic field has been investigated. The magnetic…
We present a microscopic derivation, without electrodynamical assumptions, of $B(x,y,H(t))$, $M(H(t))$, and $J_c(H(t))$, in agreement with experiments on strongly pinned superconductors, for a range of values of the density and strength of…
A simple approach to describe the levitation force measurements on melt-processed HTS bulks was developed. A couple of methods to determine the critical current density $J_c$ were introduced. The averaged $ab$-plane $J_c$ values for the…
The damping of the oscillations of a small permanent magnet (spherical shape, radius 0.1 mm) levitating between two parallel epitaxial YBCO films is measured as a function of oscillation amplitude and temperature. At small amplitudes the…
Stiffness and hysteretic energy losses are calculated for a magnetically levitating system composed of a type-II superconductor and a permanent magnet when a small vibration is produced in the system. We consider a cylindrically symmetric…
We study the dissipation of moving magnets in levitation above a superconductor. The rotation motion is analyzed using optical tracking techniques. It displays a remarkable regularity together with long damping time up to several hours. The…
Magnetization loss on a twisted superconducting (SC) tape in a ramped magnetic field is theoretically investigated through the use of a power law for the electric field--current density characteristics and a sheet current approximation.…
Recently, a novel magnetic levitation phenomenon involving two magnetically equivalent neodymium permanent magnets has been reported. In this work, we propose that this system functions as a scaled-up analog of the Levitron. The key…
Although the flux density map of a bulk superconductor provides in principle sufficient information for calculating the magnitude and the direction of the supercurrent flow, the inversion of the Biot-Savart law is ill conditioned for thick…
Magnetic levitation of superconductors is a promising platform to study quantum mechanics in the large-mass limit. One major limitation is the weak trapping potential, which results in low vibrational eigenfrequencies and increased…
By the introduction of a generalized magnetic vector potential, which contains the contributions of both the magnetic and electric parts, and the use of the Ampere's law within the quasistatic approximation as the state equation, the…
The levitation of a cylindrical permanent magnet over a high-temperature superconductor cooled by liquid nitrogen can be accompanied by spontaneous oscillations and rotation. The reason for spontaneous rotation of the magnet is…
Superconducting permanent magnets (SCs) with trapped magnetic flux are used in technical devices (motors, generators, etc.). These magnets endure repeated magnetic "shocks" during operation, which can affect their performance. In this work,…
This article presents a calculation of the mean electromotive force arising from general small-scale magnetohydrodynamical turbulence, within the framework of the second-order correlation approximation. With the goal of improving…
A permanent magnet levitating over a superconductor is found to spontaneously spin, overcoming resistance to air friction. We explain the physics behind this remarkable effect.