Dimensionality of vortex solid and liquid phases in single crystals of Bi 2Sr 2CaCu 2O 8+ δ studied by the resistivity measurements

Abstract

The anisotropy of the vortex liquid and vortex solid phases in Bi 2Sr 2CaCu 2O 8+ δ single crystal placed in tilted magnetic fields is studied by the in-plane resistivity measurements probing the true bulk properties by using the Corbino geometry of the electrical contacts. It is found that the anisotropy parameter jumps at the vortex lattice melting transition, implying the different dimensionality of the vortex solid and the vortex liquid phases. With increasing magnetic field deeper in the vortex liquid phase, the anisotropy gradually decreases without dramatic changes.