Nonlocal in-plane resistance in high-Tc superconducting films in the vicinity of a Kosterlitz-Thouless-type transition

The authors have measured the nonlocal in-plane resistance in high-Tc superconducting YBa2Cu3O7-d films. The results obtained in zero magnetic field show a negative nonlocal resistance in the vicinity of the Kosterlitz-Thouless-type vortex-antivortex unbinding transition, as it was predicted recently by Wortis and Huse. They also found that the negative nonlocal resistance takes place within a certain domain of the current-temperature diagram. The findings indicate that nonlocal measurements in ''planar'' geometry can be a new method to study vortex dynamics in superconductors