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Determination of the energy of the Dzyaloshinskii-Moriya interaction in [Co/Pd(111)]5 superlattices with different Co thickness by micromagnetic simulations of labyrinth domain structures

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 نشر من قبل Aleksandr Davydenko
 تاريخ النشر 2019
  مجال البحث فيزياء
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Determination of the energy of Dzyaloshinskii-Moriya interaction along with a definition of the basic magnetic characteristics in ferromagnetic/nonmagnetic multilayered systems are both required for the construction of a magnetic skyrmion recording medium. A method for estimating the energy of the effective Dzyaloshinskii-Moriya interaction which compared the periodicities of micromagnetically simulated and experimentally measured demagnetized domain structures was shown in a current paper. Symmetric epitaxial [Co/Pd(111)]5 superlattices with Co layers of varying thickness were used as the system for investigation. The structural and magnetic properties of epitaxial [Co(dCo)/Pd]5 superlattices with different Co layers thicknesses were comprehensively investigated. The dependence of the energy of effective Dzyaloshinskii-Moriya interaction on the thickness of the Co layers in the [Co(dCo)/Pd]5 multilayered structures was determined. The relationship between Dzyaloshinskii-Moriya interaction and asymmetry of the strains between the bottom Pd/Co and top Co/Pd interfaces was discussed. The simulation parameters and the demagnetization approach prior to measuring the magnetic structure influenced the obtained results. Necessity of setting all the layers in micromagnetic simulations was established. The significant influence of interlayer dipolar coupling on the periodicity of simulated labyrinth domain structures was also confirmed.

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