Magnetization process and domains in MTJ

Abstract

The magnetization process and domain structure of free layers in as deposited and annealed magnetic tunnel junctions (MTJ) of Si/Ta/Cu/Ta/NiFe/Cu/IrMn(10)/CoFe(2.5)/Al-O(1.5)/CoFe(2.5)/NiFe(t)/Ta, where t = 10, 30 and 100 nm, were investigated by Kerr microscopy, R-VSM and MOKE magnetometers. Different types of domain patterns observed in free layers (CoFe(2.5)/NiFe(t)) depending on the mutual relation between interlayer coupling energy and free layer magnetostatic energy. For as deposited samples fuzzy domains with fine irregular "patches" pattern, typical for weak interlayer coupling, are observed. Annealed MTJs, however, are characterized by large domains superimposed by crossed stripes, which led to the blocking of coherent rotation of magnetization.

Field-Free Spin-Orbit-Torque Switching in Co / Pt / Co Multilayer with Mixed Magnetic Anisotropies

“…In addition, these two layers are ferromagnetically coupled, and the energy of this coupling varies with t P t . 20 To quantitatively determine the coupling energy, AHE curves for different Pt spacer were modelled using macrospin approach, 29 and the energy values are depicted in Fig. 4(c).…”

Electric-field-assisted non-volatile magnetic switching in a magnetoelectronic hybrid structure

“…2.3 and 2.6 , 2.3 and 2.6 . It is mentionable that the magnetic switching process of the parallel (antiparallel) to antiparallel (parallel) state with the H-field bias is completed through the domain wall formation and propagation under both 0 kV/cm and 6 kV/cm (see Figure S16 in the supplemental information ), resulting in a sharp magnetization reversal in the vicinity of the switching fields ( Czapkiewicz et al., 2004 ; Ba et al, 2021 ). This simulation result is well consistent with our aforementioned experimental observation.…”