Investigation on different contributions to the magnetic irreversibility in Bi2Sr2CaCu2O8 single crystals

Research paper by D. Fiorani, V. A. Rybachuk, A. M. Testa, A. V. Kalinov, V. A. Murashov

Indexed on: 01 Mar '96Published on: 01 Mar '96Published in: Czechoslovak Journal of Physics


Hysteresis cycles and relaxation measurements as a function of temperature and field are reported for a very thin Bi2Sr2CaCu2O8 single crystal (thickness=5 μm). A fishtail effect was observed between 15 and 26 K at a field of ≈400 Oe, at which the relaxation rate was found to rapidly increase. The observed behaviour gives evidence of a field-induced 3d-2d dimensional crossover in the vortex lattice in presence of different sources of irreversibility (point and extended planar defects, surface barriers), each of them dominating in different regions of the B-T phase diagram.