Microwave surface resistance in BSCCO crystal: magnetic field and angular measurement.

We report on measurement of the microwave surface resistance R-s at 48 GHz on a BSCCO (2212 phase) crystal. We describe the procedure developed to perform measurements on crystals by the use of a resonant cavity with end-wall-replacement technique. The measurements are taken as a function of the temperature, magnetic field and angle theta between the field orientation and the (a,b) planes. The measured R-s is strongly anisotropic. The overall angular behavior reasonably follows the sin theta scaling rule, but deviation from this simple behavior appears approaching the parallel orientation. When the field is parallel to the (a,b) planes, a local maximum is observed in R-s, instead of a minimum. Finally, we show that the magnetic field dependence of R-s cannot be easily reconciled with existing theories for the motion of rigid flux lines.