Magnetic tunnel junctions stabilized by modified synthetic antiferromagnets

In a conventional magnetic tunnel junction (MTJ) using a synthetic antiferromagnet (SAF), the stray field from the pinned layer often causes poor switching asymmetry due to the thickness difference between two ferromagnetic layers separated by a Ru spacer [1]. To attain good bias point control, a modified synthetic antiferromagnet (MSAF) structure, consisting of an additional Ru/ferromagnet onto the SAF, was suggested. In this computational simulation study, we evaluated MR transfer characteristics with an attention paid on the bias point of an MTJ with an MSAF using LLG equation and we could find the better switching behaviour of free layer in MSAF as the size decreases.