相关论文: Mathematical analysis of a flux-jump model in supe…
A theoretical study of dynamics of small thermal and electromagnetic perturbations in type-II superconductors in the flux creep regime with a nonlinear current-voltage characteristics is performed. For this purpose, the space-time evolution…
Magnetic flux jumps in textured Bi2Sr2CaCu2O(8+d) have been studied by means of magnetization measurements in the temperature range between 1.95 K and Tc, in an external magnetic field up to 9 T. Flux jumps were found in the temperature…
A trapped magnetic field of greater than 3 T has been achieved in a single grain GdBa2Cu3O7-{\delta} (GdBaCuO) bulk superconductor of diameter 30 mm by employing pulsed field magnetisation (PFM). The magnet system is portable and operates…
In this report, the temperature distribution in the critical state of hard superconductors is investigated in the quasi-stationary approximation. It is shown that the temperature profile can be essentially inhomogeneous in the sample, which…
The understanding of flux jumps in the high temperature superconductors is of importance since the occurrence of these jumps may limit the perspectives of the practical use of these materials. In this work we present the experimental study…
We calculate the temperature and magnetic field distributions in a bulk superconductor during the process of pulsed-field magnetic activation. The calculations are based on the heat diffusion equation with account of the heat produced by…
When a superconducting ring encloses a magnetic flux that is not an integer multiple of half the quantum of flux, a voltage arises in the direction perpendicular to the temperature gradient. This effect is entirely due to thermal…
Rings are a model system for studying phase coherence in one dimension. Superconducting rings have states with uniform phase windings that are integer multiples of 2$\pi$ called fluxoid states. When the energy difference between these…
The authors report magnetic measurements of fluxoid transitions in mesoscopic, superconducting aluminum rings. The transitions are induced by applying a flux to the ring so that the induced supercurrent approaches the critical current. In a…
When a superconducting radiofrequency cavity is cooled through its critical temperature, ambient magnetic flux can become "frozen in" to the superconductor, resulting in degradation of the quality factor. This is especially problematic in…
We perform a numeric study of the flux transitions in a superconducting ring at fixed temperature, while the applied field is swept at an ideally slow rate. The current around the ring and its free energy are evaluated. We partially explain…
We theoretically study the behavior of the critical current of a thermally-biased tunnel Josephson junction with a particular design, in which the electrodes of the junction are enclosed in two different superconducting loops pierced by…
The goal of this research is the study of the thermomagnetic consequences in isotropic type-II superconductors, subjected to multi-component magnetic fields $\mathbf{H}_a = H_{ay}\hat{y}+H_{az}\hat{z}$, because the instability field…
Magnetothermal instabilities are one of the peculiar phenomena of interest in conventional type-II, as well as in high-$T_c$ superconductors. In the present paper we attempt to analyze the nature and origin of the magnetothermal…
Nonlinear multi-field coupling as an intrinsic property of complex physical systems often leads to abrupt and undesired instabilities. For current-ramped high-field Nb3Sn magnets, frequent flux jumps are observed, which easily causes…
A theory for the electromagnetic response of type-II superconductors close beyond the critical state is presented. Our formulation relies on general physical principles applied to the superconductor as a thermodynamic system. Equilibrium…
By doing magnetization measurements during magnetic field sweeps on thin films of the new superconductor $MgB_2$, it is found that in a low temperature and low field region small flux jumps are taking place. This effect strongly suppresses…
Employing the standard worldline-vortex mapping, we conclude that at the critical temperature, superconductors demonstrate the magneto-halon effect with respect to the quantized net magnetic flux generated by a solenoid inserted into the…
We develop a fast numerical procedure for analysis of nonlinear and nonlocal electrodynamics of type-II superconducting films in transverse magnetic fields taking into account realistic boundary conditions. Using this procedure we explore…
Fluctuations are important near phase transitions, where they can be difficult to describe quantitatively. Superconductivity in mesoscopic rings is particularly intriguing because the critical temperature is an oscillatory function of…