Focused Magneto-optical Kerr Effect measurement of single pseudo spin-valve ring elements

This paper, presents a study of a range of micrometer-scale PSV (pseudo spin-valve) ring elements using focused magneto-optic Kerr effect (FMOKE) magnetometery. The rings were patterned using e-beam lithography and lift off processing and have a layer configuration of 8 nm Co/6.5 nm Cu/6 nm permalloy. The laser spot of the FMOKE magnetometer can be focused to a spot size of approximately 4 mum (full width half maximum) allowing the measurement of individual ring elements. This approach allows the resolution of fine details in hysteresis loops which would be lost in the averaging of more traditional, array based, measurement techniques.