Magnetoresistance and hall effect characterisation on magnetic thin films multilayers

We have performed both Hall effect, and magnetoresistance measurements on thin films of Permalloy (Py 10 nm) and Py(t(Py))/Cu(t(Cu))/Py(t(Py)) multilayers deposited on thermally oxidized Si substrates, where t(Py)=4 and 10 nm and t(Cu)=4 and 8 nm. The measurements were made at room temperature in a setup that allows us to perform both Hall effect and magnetoresistance measurements. The Hall effect measurements were performed varying the angle, Deltatheta, between the magnetic field direction and the normal to the film plane from 0 to 90 degrees, ne measured voltages present hysteresis loops at low magnetic field even for Deltatheta=thetadegrees. From these measurements we can obtain some information regarding the magnetic properties of our samples.