ANGLE-RESOLVED RESISTIVITY MEASUREMENTS IN A BI-2212 SINGLE-CRYSTAL WITH INCLINED COLUMNAR DEFECTS

Transport measurements in the sc-called ''Top'' and ''Cross'' configur ations are used to study the behaviour of the vortex lines in a heavy ions irradiated (at 45 degrees with respect to the ab plane) Bi-2212 s ingle crystal. From the resistance curves as a function of the tempera ture for several magnetic fields we derived the Bose glass line transi tion. In this analysis the critical exponents were found to be nearly the same in the two configurations. Moreover, from a comparison betwee n the R(T, 45 degrees) and R(T, -45 degrees) (magnetic field parallel and perpendicular to the columnar defects) we defined a crossover line T-Dir (B) above which the directional effect disappears.