Statistical study of domain-wall depinning induced by magnetic field and current in an epitaxial Co/Ni-based spin-valve wire

International audienceWe investigated the current-induced domain-wall (DW) depinning for various applied magnetic fields on a well-indentified single pinning site in epitaxial Co/Ni-based spin-valve wire of micronic width. The DW depinning process occurs with thermal activation involving a single energy barrier associated with a single pinning site. By measuring the DW depinning probability for various positive and negative applied fields (H+,H−) and currents (I+,I−), we built a map highlighting regions where spin-transfer torque (STT) effect, Joule heating, and Oersted field dominate. We then propose a method to quantify characteristic parameters of both adiabatic and nonadiabatic components of STT despite the presence of other effects due to current injection. The suitability of the method is validated by the fact the extracted values are close to those obtained previously on single [Co/Ni] layer where Oersted field and Joule effects were negligible