Vortex matter in a hybrid superconducting/ferromagnetic nanostructure

Autor:	Qinghua Chen, C Carballeira, Victor Moshchalkov
Rok vydání:	2009
Předmět:	Physics Superconductivity Phase boundary Condensed matter physics Condensed Matter::Superconductivity Ginzburg–Landau theory Boundary value problem Vorticity Condensed Matter Physics Electronic Optical and Magnetic Materials Vortex Magnetic field Vector potential
Zdroj:	Physical Review B. 79
ISSN:	1550-235X 1098-0121
DOI:	10.1103/physrevb.79.104520
Popis:	By using a gauge transformation of the vector potential that accounts for the superconducting/vacuum boundary condition, we solve the linear and nonlinear Ginzburg-Landau equations to calculate the phase diagram of the hybrid superconducting/ferromagnetic nanostructure formed by a superconducting microsquare with a magnetic disk on top. Close to the normal/superconducting phase boundary TcH we observe that the competition between the applied magnetic field and the inhomogeneous field of the disk strongly affects the vortex nucleation. As a consequence, different symmetry constraints are imposed on the vortex patterns at TcH, leading to the exclusion of some vorticity values allowed in the no-dot case. The dot also influences the evolution with temperature of the vortex states deep in the superconducting phase, giving rise to instability processes that differ from those previously found in individual microsuperconductors and that may involve the spontaneous generation of additional vortices. Besides, the dot also forces the vortex matter in this hybrid nanostructure to behave similarly to the case of an individual microdisk in some regions of the phase diagram.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::2dd1feab8f903db1691768c35fe085b8 https://doi.org/10.1103/physrevb.79.104520 Zobrazit plný text záznamu