Vortex dynamics and phase diagram of BSCCO in the presence of columnar defects

Current-voltage characteristics are investigated in BiSr2CaCu2O8 single crystals irradiated parallel to the c-axis with 5.8 GeV Pb ions. For weak magnetic field (B < B-Phi), we find that isothermal I-V curves scale according to the Bose-glass (BG) theory. Field and sample independent critical exponent z' = 5.27 +/- 0.05 and v' = 1.30 +/- 0.07 have been found. The magnetic field dependence of the BG melting line T-BG (B), derived from critical scaling analysis, is in good agreement with the Lindemann criterion which accounts for the contribution of correlated disorder. Two characteristic temperatures T-0 approximate to 0.72 T-c (f approximate to 0.8) and T-1 approximate to 0.83 T-c (f approximate to 1/3), beyond which the vortex system is increasingly dominated by vortex-vortex interactions thigh held) or thermal fluctuations (high temperature), are identified. We obtain good quantitative agreement between our experimental data and the predictions of the Bose-glass theory for correlated disorder.