Simultaneous magnetic force microscopy and magnetoresistance characterization of a magnetic tunnel junction with in situ applied field

For the first time, both the magnetoelectronic properties and the magnetic domain structure of a magnetic tunnel junction (MTJ) have been characterized simultaneously. In situ tunneling magnetoresistanee measurements for a spin-dependent tunnel junction were directly compared to magnetic domain behavior imaged using magnetic force microscopy (MFM) under the same applied fields, allowing for detailed investigation of electronic behavior relative to magnetic behavior. From the results, it was found that the resistance in the hysteretic field range (less than the coercivity of Hc = 800 A/m or 10 Oe) corresponded with the complex magnetic domain behavior observed in the MFM images and qualitatively matched micromagnetically modeled junctions. Index Terms--Domain structures, magnetic force microscopy (MFM), magnetoresistance, spin-dependent transport.