Fluctuation magnetoconductivity of BSCCO-2212 films in parallel magnetic field

The in-plane (delta sigma (ab)(T,H)) and out-of-plane (delta sigma (c)(T,H) ) components of the magnetoconductivity tenser of Bi2Sr2CaCu2O8+x films hav e been simultaneously measured in magnetic fields parallel to the film cond ucting planes (B less than or equal to 1 T). A negative c-axis magnetoresis tance is measured for the first time in this geometry. Both delta sigma (ab ) and delta sigma (c) are well described by the fluctuation theory in the t emperature range T-c < T < T-c + 20 K, using a single set of microscopical parameters for both directions. The negative c-axis magnetoresistance in th e field parallel to conducting layers is shown to be induced by the density of states Zeeman fluctuation contribution. (C) 2001 Elsevier Science B.V. All rights reserved.