Dependence of critical current on field angle in off-c-axis grown Bi2Sr2CaCu2O8 film

Critical current measurements for varying angles of applied field have been performed on Bi2Sr2CaCu2O8 thin films grown on 10 degrees vicinal (001) su bstrates. Measurements were performed on current tracks orientated both par allel (L) and transverse (T) to the vicinal steps. No Josephson vortex chan neling effect was observed, in contrast to results previously obtained on b oth oxygenated and deoxygenated YBa2Cu3O7-delta films grown on vicinal subs trates. In addition, no force-free peak was observed when the applied field was parallel to the current. This provides experimental evidence that ther e is a difference between the pancake coupling mechanism in YBa2Cu3O7-delta at small field angles where Josephson vortices are present and that in Bi2 Sr2CaCu2O8. (C) 2000 American Institute of Physics. [S0003- 6951(00)04237-6 ].