Flux lattice melting and nonlocal electrodynamics in YBa2Cu3O7-delta single crystal in a magnetic field parallel CuO2 layers

Twinned single crystal YBa2Cu3O7-delta has been investigated by the c-axis transport measurements with eight contacts and B parallel to ab planes. Thi s experimental geometry allows studies of the vortex velocity correlations both parallel and perpendicular to the applied magnetic field. A flux-line lattice (FLL) parallel to the ab planes is found to melt into a disentangle d vortex liquid, and for B less than or equal to 2 T; this melting occurs i n a moving FLL above the irreversibility line. A nonlocal contribution to t he transport properties is also inferred from the results. [S0163-1829(99)0 4645-7].