相关论文: Mesoscopic Superconducting Disc with Short-Range C…
We investigate the influence of columnar defects in layered superconductors on the thermally activated penetration of pancake vortices through the surface barrier. Columnar defects, located near the surface, facilitate penetration of…
The influence of the geometry of a thin superconducting sample on the penetration of the magnetic field lines and the arrangement of vortices are investigated theoretically. We compare superconducting disks, squares and triangles with the…
Order-disorder transitions take place in many physical systems, but observing them in detail in real materials is difficult. In two- or quasi-two-dimensional systems, the transition has been studied by computer simulations and…
The vortex states in a thin mesoscopic disk are investigated within the phenomenological Ginzburg-Landau theory in the presence of different ''model'' magnetic field profiles with zero average field which may result from a ferromagnetic…
Using the non-linear Ginzburg-Landau (GL) eqs. type I superconducting disks of finite radius ($R$) and thickness ($d$) are studied in a perpendicular magnetic field. Depending on $R$ and $d$, first or second order phase transitions are…
We analyze the origin of the parabolic background of magnetoresistance oscillations measured in finite-width superconducting mesoscopic rings with input and output stubs and in patterned films. The transmission model explaining the…
Persistent scaling behavior of magnetization in layered high $T_c$ superconductors with short--range columnar defects is explained within the Ginzburg Landau theory. In the weak field region, the scaling function differs from that of a…
Defects introduced in ferromagnetic nanodisks may deeply affect the structure and dynamics of stable vortex-like magnetization. Here, analytical techniques are used for studying, among other dynamical aspects, how a small cylindrical cavity…
Solutions of Ginzburg-Landau eqns. coupled with three dimensional Maxwell eqns. reveal intriguing magnetic response of small superconducting particles, qualitatively different from the two dimensional approximation but in agreement with…
We study theoretically the vortex matter structure in low dimensional (LD) systems with superconducting order induced by proximity to a bulk superconductor. We analyze the effects of microscopic coupling mechanisms between the two systems…
The observation of vortices in superconductors was a major breakthrough in developing the conceptual background for superconducting applications. Each vortex carries a flux quantum, and the magnetic field radially decreases from the center.…
Phase transitions in superconducting mesoscopic disks have been studied over the H-T phase diagram through heat capacity measurement of an array of independent aluminium disks. These disks exhibit non periodic modulations versus H of the…
A rather general enhancement of superconductivity is demonstrated in a hybrid structure consisting of submicron superconducting (SC) sample combined with an in-plane ferromagnet (FM). The superconducting state resists much higher applied…
Direct observation of vortices by the scanning SQUID microscopy was made on large mesoscopic disks of an amorphous MoGe thin film. Owing to the weak pinning nature of the amorphous film, vortices are able to form geometry induced,…
The vortex states in a thin mesoscopic disk are investigated within the phenomenological Ginzburg-Landau theory in the presence of a step-like external magnetic field with zero average which could model the field resulting from a…
In mesoscopic two-gap superconductors with sizes of the order of the coherence length noncomposite vortices are found to be thermodynamically stable in a large domain of the $T - H$ phase diagram. In these phases the vortex cores of one…
Solving numerically the 3D non linear Ginzburg-Landau (GL) equations, we study equilibrium and nonequilibrium phase transitions between different superconducting states of mesoscopic disks which are thinner than the coherence length and the…
Defects in the atomic lattice of solids are sometimes desired. For example, atomic vacancies, single ones or more elaborated defective structures, can generate localized magnetic moments in a non magnetic crystalline lattice. Increasing…
The electronic structure of the giant vortex states in a mesoscopic superconducting disk is studied in a dirty limit using the Usadel approach. The local density of states profiles are shown to be strongly affected by the effect of…
Scanning Hall probe and local Hall magnetometry measurements have been used to investigate flux distributions in large mesoscopic superconducting disks with sizes that lie near the crossover between the bulk and mesoscopic vortex regimes.…