Measurement of magnetization using domain compressibility in CoFeB films with perpendicular anisotropy

N. Vernier (1) , J-P Adam (1) , S. Eimer (1) , G. Agnus (1) , T. Devolder (1) , Thomas Hauet (2) , B. Ocker (3) , F. Garcia (1) , D. Ravelosona (1)

1 IEF - Institut d'électronique fondamentale
2 IJL - Institut Jean Lamour
3 Singulus technology AG

We present a method to map the saturation magnetization of soft ultrathin films with perpendicular anisotropy, and we illustrate it to assess the compositional dependence of the magnetization of CoFeB(1 nm)/MgO films. The method relies on the measurement of the dipolar repulsion of parallel domain walls that define a linear domain. The film magnetization is linked to the field compressibility of the domain. The method also yields the minimal distance between two walls before their merging, which sets a practical limit to the storage density in spintronic devices using domain walls as storage entities.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

N. Vernier, J-P Adam, S. Eimer, G. Agnus, T. Devolder, et al.. Measurement of magnetization using domain compressibility in CoFeB films with perpendicular anisotropy. Applied Physics Letters, 2014, 104 (12), pp.122404 ⟨10.1063/1.4869482⟩. ⟨hal-01282865⟩