In-situ Lorentz microscopy studies of spin-valve structures

Lorentz electron microscopy, including a quantitative magnetisation-mapping technique, has been used to study the local magnetisation reversal mechanism in active spin-valve devices for correlation with the giant magnetoresistance and domain structure. Varying various parameters such as device size, applied current value and direction of easy-axis have been found to have an effect on the magnetisation reversal mechanism and on the GMR curve. Index terms - Lorentz microscopy, magnetisation reversal, spin-valve elements, giant magnetoresistance