Quasi-antiferromagnetic multilayer stacks with 90 degree coupling mediated by thin Fe oxide spacers

Abstract

We fabricated quasiantiferromagnetic (quasi-AFM) layers with alternating antiparallel magnetization in the neighboring domains via 90 degrees magnetic coupling through an fe-o layer. we investigated the magnetic properties and the relationship between the magnetic domain size and the 90 degrees magnetic coupling via experiments and calculations. two types of samples with a ru buffer and a (ni80fe20)cr-40 buffer were prepared, and we found that with the nifecr buffer, the sample has a flatter fe-o layer, leading to stronger 90 degrees magnetic coupling and a smaller domain size compared with the ru buffer sample. this trend is well explained by the bilinear and biquadratic coupling coefficients, a(12) and b-12, in landau-lifshitz-gilbert simulations, suggesting the possibility of using both afm and fm properties by controlling the quasi-afm domain size.