Abstract :
Current–voltage characteristics are investigated in BiSr2Ca1−xYxCu2O8 crystals irradiated parallel to the c-axis with 5.8 GeV Pb ions. Over a wide range of filling fractions 0.026≤f≤1, the I–V isotherm curves near the superconducting transition are consistent with the Bose-glass scaling theory. Field and matching field independent critical exponent values z′=5.27±0.05 and ν′=1.30±0.07 have been found. This result is in good agreement with the well-established universality rules for the critical exponents at standard second-order transition. The glass line, derived from scaling analysis, is well described by the Lindemann criterion that accounts for the contribution of correlated disorder. Two characteristic temperatures, beyond which the vortex system is increasingly dominated by vortex–vortex interactions or thermal fluctuations, respectively, are identified. In these domains, the Bose-glass melting line merges the pristine melting line.
