Observation of Splintered Josephson Vortices at Grain Boundaries in [Formula presented]

Abstract

We have directly observed well-separated Josephson vortex splinters with unquantized magnetic flux at asymmetric [Formula presented] grain boundaries in [Formula presented] films by imaging magnetic flux with scanning SQUID microscopy. The existence of these splinter vortices has been predicted and is well described by a model based on [Formula presented] pairing symmetry and facetting of the grain boundary on a length scale shorter than the Josephson penetration depth. © 2002 The American Physical Society.