We examine the substructures of magnetic domain walls (DWs) in [Pt/(Co/Ni)M/Ir]N multi-layers using a combination of micromagnetic theory and Lorentz transmission electron microscopy (LTEM). Thermal stability calculations of Q=±1 substructures (2-π vertical Bloch lines (VBLs) and DW skyrmions) were performed using a geodesic nudged elastic band (GNEB) model, which supports their metastability at room temperature. Experimental variation in strength of the interfacial Dzyaloshinskii-Moriya interaction (DMI) and film thickness reveals conditions under which these substructures are present and enables the formation of a magnetic phase diagram. Reduced thickness is found to favor Q=±1 substructures likely due to the suppression of hybrid DWs. The results from this study provide an important framework for examining 1-D DW substructures in chiral magnetic materials.
@article{arxiv.2004.07888,
title = {Magnetic domain wall substructures in Pt/Co/Ni/Ir multi-layers},
author = {Maxwell Li and Arjun Sapkota and Anish Rai and Ashok Pokhrel and Tim Mewes and Claudia Mewes and Di Xiao and Marc De Graef and Vincent Sokalski},
journal= {arXiv preprint arXiv:2004.07888},
year = {2021}
}