Perpendicular transport and magnetic properties in patterned multilayer magnetic microstructures (invited)

Using micron‐level photolithography, we have prepared a set of patterned multilayer samples which have the form [Co/Cu/NiFeCo/Cu]×10 and which permit perpendicular current transport through the structure. Based on vibrating sample magnetometry, the multilayer stacks show a loss of ≊2 A of magnetic material at each interface. The magnetoresistance was measured as a function of temperature, magnetic layer thickness, and element size and the ΔR/R values range up to 8% at 300 K and 18% at 10 K. The thickness dependent data are modeled using an extension of existing methods and can be fit using comparable resistivity, interface resistance, and spin asymmetry parameters. The magnetic fringe fields of the elements have an important effect on the observed R vs H curves.