2013/08/08 by Jacob Torrejón, Jacob Torrejon, Junyeon Kim +12 · 1 citation
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnesium Oxide Properties and Applications #Magnetic properties of thin films #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Multiferroics and related materials #ZnO doping and properties #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.1308.1751
arxiv created 2013/08/08 · openalex publication_date 2013/08/08 · arxiv updated 2013/08/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Recent advances in the understanding of spin orbital effects in ultrathin magnetic heterostructures have opened new paradigms to control magnetic moments electrically. The Dzyaloshinskii-Moriya interaction (DMI) is said to play a key role in forming a Neel-type domain wall that can be driven by the spin Hall torque, a torque resulting from the spin current generated in a neighboring non-magnetic layer via the spin Hall effect. Here we show that the sign of the DMI, which determines the direction to which a domain wall moves with current, can be changed by modifying the adjacent non-magnetic layer. We find that the sense of rotation of a domain wall spiral is reversed when the Ta underlayer is doped with nitrogen in Ta|CoFeB|MgO heterostructures. The spin Hall angle of the Ta and nitrogen doped Ta underlayers carry the same sign, suggesting that the sign of the DMI is defined at the interface. Depending on the sense of rotation, spin transfer torque and spin Hall torque can either compete or assist each other, thus influencing the efficiency of moving domain walls with current.