Low-temperature magnetic force microscopy has been used to visualize spontaneous formation of vortex-antivortex pairs in hybrid ferromagnet/superconductor systems. Vortex-antivortex pairs are induced by the periodic stray field of the ferromagnet. We find general equilibrium conditions for which spontaneous vortex-antivortex pairs are formed during zero-field cooling of the hybrid ferromagnet/superconductor bilayers. Vortices can be generated by the ferromagnet domains in the absence of an external field and they are thermodynamically stable for values of the stray field and the period of the stripe magnetic domains that exceed a certain threshold.
Imaging the spontaneous formation of vortex-antivortex pairs in planar superconductor/ferromagnet hybrid structures
Bobba F;Giubileo F;Cucolo A M
2011
Abstract
Low-temperature magnetic force microscopy has been used to visualize spontaneous formation of vortex-antivortex pairs in hybrid ferromagnet/superconductor systems. Vortex-antivortex pairs are induced by the periodic stray field of the ferromagnet. We find general equilibrium conditions for which spontaneous vortex-antivortex pairs are formed during zero-field cooling of the hybrid ferromagnet/superconductor bilayers. Vortices can be generated by the ferromagnet domains in the absence of an external field and they are thermodynamically stable for values of the stray field and the period of the stripe magnetic domains that exceed a certain threshold.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
