Manipulation of single vortices in YBa2Cu3O6.354 with a locally applied magnetic field

We demonstrate the controlled, reversible manipulation of individual vortices in a superconductor with a locally applied magnetic field. The local field is supplied by a field coil on a superconducting quantum interference device (SQUID). The SQUID is used to image the vortices before and after moving. This device can be used both to push individual vortices and to create individual vortex–antivortex pairs. We calculate the force applied on a rigid vortex and find that ∼0.5 pN is necessary to move vortices in underdoped single crystals of YBa2Cu3O6.354 with Tc∼ 12 K.