Eects of Columnar and Point Defects on Magnetic Hysteresis Curves Produced by Three-dimensional Vortices in Layered Superconductors
نویسندگان
چکیده
Using parallel three-dimensional molecular dynamics simulations of line-like coupled pancake vortices, we consider the eect of inter-layer coupling strength and pinning correlation on the magnetization curves of anisotropic super-conductors. Columnar pins produce the largest critical current and are insensitive to layer interaction strength. Point pins are increasingly eective at pinning the vortices as the inter-layer interaction strength drops.
منابع مشابه
Localized Flux Lines and the Bose Glass
Columnar defects provide effective pinning centers for magnetic flux lines in high–Tc superconductors. Utilizing a mapping of the statistical mechanics of directed lines to the quantum mechanics of two–dimensional bosons, one expects an entangled flux liquid phase at high temperatures, separated by a second–order localization transition from a low–temperature “Bose glass” phase with infinite ti...
متن کاملNumerical calculation of the vortex–columnar-defect interaction and critical currents in extreme type-II superconductors—a two-dimensional model based on the Ginzburg–Landau approximation
We extend our previous one-dimensional Ginzburg–Landau calculations of the pinning energy of vortices to two dimensions, in order to achieve an understanding of the pinning forces exerted on vortices by defects. By minimizing the free energy using a relaxation scheme, we obtain the spatial variation of the order parameter and supercurrents for a vortex in the vicinity of a cylindrical defect in...
متن کاملnd - m at . s up r - co n ] 2 9 Ju l 1 99 9 Hall tunneling of vortices in superclean superconductors
We discuss the main features of Hall tunneling of pancake vortices in super-clean high-T c superconductors. The general formalism for the calculation of the lifetime of a vortex pinned in a metastable configuration is described. The results are applied to the problem of quantum tunneling of a pancake vortex from a columnar defect in the limit of a small driving current. An external magnetic fie...
متن کاملLocal probe of vortex pinning energies in the Bose glass.
Columnar defects provide strong pinning centers for vortices in high-T, superconductors, increasing global critical currents. Using a magnetometer array of micron dimensions, we characterize the local field profiles in untwinned single crystals of YBa2Cu307 ~ with equivalent columnar defect densities B&. We find that the critical current is large only where the internal magnetic field B~B&. In ...
متن کاملImaging atomic-scale effects of high-energy ion irradiation on superconductivity and vortex pinning in Fe(Se,Te)
Maximizing the sustainable supercurrent density, J C, is crucial to high-current applications of superconductivity. To achieve this, preventing dissipative motion of quantized vortices is key. Irradiation of superconductors with high-energy heavy ions can be used to create nanoscale defects that act as deep pinning potentials for vortices. This approach holds unique promise for high-current app...
متن کامل