|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals and Materials
||K-108: Observation of Topological Defects in Synthetic Antiferromagnets with Inverted Dzyaloshinskii-moriya Interaction
||Nisrit Pandey, Maxwell Li, Marc De Graef, Vincent Sokalski
|On-Site Speaker (Planned)
Synthetic AntiFerromagnets (SAFs) show tremendous potential for developing efficient racetrack memory, where domain wall (DW) velocities have reported to be much higher than their ferromagnetic (FM) counterparts. Each layer of the SAF is based on a HM/FM/HM multi-layer where the Heavy Metal (HM) is either Pt or Ir and FM is a Co/Ni multi-layer. This work studies a new type of DW, where top and bottom layer of SAF have parallel internal DW magnetization despite being AF coupled due to an inverted Dzyaloshinskii-Moriya Interaction (DMI) sign. Experimental results on SAFs with tunable exchange coupling strength and DMI are presented along with Lorentz TEM images of DWs. Initial results show these DWs adopt a tiger-tail pattern and walls in top and bottom layer clearly separate with application of a field. This work studies topological defects on SAF DWs and their detection with a combination of micromagnetic simulations and Lorentz TEM.