Vortex dynamics in heavy-ion-irradiated single crystals of Bi_2Sr_2CaCu_2O_(8+δ) and Bi_(1.8)Pb_(0.2)Sr_2CaCu_2O_(8+δ): Comparison from transport measurements

摘要

Magnetotransport measurements were carried out on irradiated Bi_2Sr_2CaCu_2O_(8+δ) and Bi_(1.8)Pb_(0.2)Sr_2CaCu_2O_(8+δ) single crystals in order to investigate their vortex pinning properties. A three-dimensional Bose-glass transition with the same critical exponents is present in both cases. The occurrence of the Bose-glass transition in the case of highly anisotropic Bi_2Sr_2CaCu_2O_(8+δ)(γ > 200) supports the existence of a strong interlayer coupling of the pancake vortices due to columnar defects up to B_φ.