Angle dependence of magnetoresistance peaks in thin nickel films

The angle dependence of magnetoresistance (MR) peaks in thin nickel films w as investigated by rotating the sample in two different ways. The phase mix ing of the positive MR and negative MR signals was observed 1) with the sam ple located in the same plane as the field and rotated through an axis perp endicular to the field and 2) with the sample located in a plane perpendicu lar to the field and then rotated. In the latter case, the field difference between the two MR peaks increased, This behavior is well explained by the concept of effective magnetic field.