Influence of lateral geometry on magnetoresistance and magnetisation reversal in Ni80Fe20 wires

The magnetisation reversal processes and magnetoresistance behaviour in mic ron-sized Ni80Fe20 wires with triangular and rectangular modulated width ha ve been studied. The wires were fabricated by electron beam lithography and a lift-off process. A combination of magnetic force microscopy (MFM), magn eto-optical Kerr effect (MOKE) and magnetoresistance (MR) measurements show s that the lateral geometry of the wires greatly influences the magnetic an d transport properties. The width modulations modify not only the shape-dep endent demagnetising fields, but also the current density. The correlation between the lateral geometry, the magnetic and the transport properties is discussed based on MFM, MOKE and MR results.