相关论文: Weak- to strong pinning crossover
The mixed phase of layered superconductors with no magnetic screening is studied through a partial duality analysis of the corresponding XY model in the presence of random pinning centers. Sufficiently weak Josephson coupling between…
We present the experimental observation of magnetic field line curvature at the surface of a superconducting film by local quantitative magneto-optics. In addition to the knowledge of the full induction field at the superconductor surface…
Superconductivity in the heavy-fermion metal UTe2 survives the application of very high magnetic fields, presenting both an intriguing puzzle and an experimental challenge. The strong, non-perturbative influence of the magnetic field…
We derive the connection between the Cooperon problem in weak localization theory and the random matrix description of type-II superconductors. As magnetic field and disorder increase, an extreme type-II superconductor crosses over from a…
The vortex-lattice melting line in three-dimensional type-II superconductors with pinning is derived by equating the free energies of the vortex system in the solid and liquid phases. We account for the elastic and pinning energies and the…
Particles occupying sites of a random lattice present density fluctuations at all length scales. It has been proposed that increasing interparticle interactions reduces long range density fluctuations, deviating from random behaviour. This…
Enhancement of flux pinning by magnetic nanoparticles embedded into the bulk of type-2 superconductor is studied both theoretically and experimentally. Magnetic part of the pinning force associated with the interaction between a spherical…
We study vortex pinning in layered type-II superconductors in the presence of uncorrelated disorder for decoupled layers. Introducing the new concept of variable-range thermal smoothing, we describe the interplay between strong pinning and…
The magnetic response of type-II superconductors can be irreversible due to two different reasons: vortex pinning and barriers for flux penetration. Even without bulk pinning and in absence of a microscopic Bean-Lingston surface barrier for…
We investigate the scaling properties of single flux lines in a random pinning landscape consisting of splayed columnar defects. Such correlated defects can be injected into Type II superconductors by inducing nuclear fission or via direct…
We identify a phase transition in the vortex system of a high-temperature superconductor with nano-columnar stacks of precipitates as strong vortex pinning centers. Above a particular, temperature-dependent field $B_X(T)$ the vortex…
The vortex hopping motion in a type-II superconductor determines the current-carrying ability and consequently the application fields of the superconductor. However, it is not clear how the vortices hop between the different pinning regions…
The vortex lattice is an ideal system to study the competition and interplay between interaction and disorder. New results on 2H-NbSe_2 (in samples of progressively increasing pinning) elucidate how pinning alters the phase boundary…
Using the time-dependent Ginzburg-Landau equation with the complex relaxation time and the Maxwell equation, we systematically examine transverse motion of vortex dynamics in the presence of pinning disorders. Consequently, in a plastic…
We use a model of vortex dynamics and collective weak pinning theory to study the residual dissipation due to trapped magnetic flux in a dirty superconductor. Using simple estimates, approximate analytical calculations, and numerical…
In order to compare magnetic and non-magnetic pinning we have nanostructured two superconducting films with regular arrays of pinning centers: Cu (non-magnetic) dots in one case, and Py (magnetic) dots in the other. For low applied magnetic…
We show numerically that in a binary system of Yukawa particles, a dispersity driven disordering transition occurs. In the presence of quenched disorder this disordering transition coincides with a marked increase in the depinning…
We discuss the low-temperature dynamics of magnetic flux lines in high-temperature superconductors in the presence of a family of parallel twin planes that contain the $c$ axis. A current applied along the twin planes drives flux motion in…
We discuss a new class of phenomena based on strong interaction between magnetic superstructures and vortices in superconductors in combined heterogeneous structures. An inhomogeneous magnetization can pin vortices or create them…
We investigate the dynamics of magnetic vortices in type II superconductors with normal state pinning sites using the Ginzburg-Landau equations. Simulation results demonstrate hopping of vortices between pinning sites, influenced by…