RIS ID
116450
Abstract
The electrodynamic behavior of isotropic superconducting Nb films cooled below their critical temperature in the presence of in-plane applied magnetic fields is investigated using magneto-optical imaging. A specially designed local flux injector is used to show that the frozen-in in-plane vortices strongly guide and enhance the penetration of perpendicular vortices, whereas their penetration across the array of in-plane vortices is essentially unchanged. This result provides the key to understanding why field-cooled square superconducting films show anisotropic nucleation of flux avalanches (jumps) along the four edges. The explanation is based on an analytical model for thermomagnetic avalanche nucleation in type-II superconducting films, and allows one to understand the entire scenario of different flux dynamics observed experimentally.
Publication Details
Colauto, F., Carmo, D., De Andrade, A. M. H., Oliveira, A. A. M., Ortiz, W. A. & Johansen, T. H. (2017). Anisotropic thermomagnetic avalanche activity in field-cooled superconducting films. Physical Review B: Condensed Matter and Materials Physics, 96 (6), 060506-1-060506-5.