Local Electrodynamics in Heavy Ion IrradiatedBi2Sr2CaCu2O8+δ

Transport measurements in the flux transformer and $c$-axis geometries are used to investigate vortex dynamics in heavy ion irradiated BSCCO crystals. In the flux transformer geometry there is a range of fields, temperatures, and angles where the primary and secondary voltages show close correspondence, as observed in YBCO. This occurs because the columnar defects suppress thermal fluctuations and decrease ${\rho }_c$. Values for ${\rho }_{\mathrm{ab}}$ and ${\rho }_c$ are extracted from the flux transformer data assuming local anisotropic electrodynamics and compared with directly measured $c$-axis data. Good agreement confirms the validity of local resistivity. This is supported by both measurement configurations indicating that ${\rho }_c$ vanishes faster than ${\rho }_{\mathrm{ab}}$.