Peculiarities of spin–orbit interaction systematically measured in FeCoB nanomagnets

This study introduces a method to measure the strength of spin–orbit interaction (SO) in a nanomagnet, investigating fundamental phenomena governing magnetic anisotropy. The method explores the fundamental property of SO in its linear proportionality to the external magnetic field, a relationship validated through experimental observation. Systematic study of SO in FeCoB nanomagnets reveals distinct SO behaviors in bulk and at an interface, substantial disparities in single- and multi-layer nanomagnets, intriguing periodic oscillations in SO strength, and the systematic relationship between SO strength, demagnetization field, and magnetic anisotropy based on surface imperfections. These findings provide crucial insights into diverse SO interaction behaviors, crucial for understanding and optimizing magnetic anisotropy and nanomagnet properties.