Agenda

Anisotropic magnetic textures in epitaxial ultra-thin films with two-fold symmetry

Mercredi 16 décembre à 11h

Link: zoom
Meeting ID: 925 6127 8022
Passcode: 000111

Topological magnetic textures such as skyrmions have been extensively studied during the last decade due to their potential application in spintronics devices. In ultrathin films systems, a key parameter to stabilize chiral topological magnetic textures is the Dzyaloshinskii-Moriya interaction (DMI), obtained at the interfaces between ferromagnetic layers and heavy-metals, promoting a unique chirality of the magnetic texture.

In this work, we focus on an ultra-thin epitaxial Au1-xPtx /Co/W(110) trilayer, a model system exhibiting perpendicular magnetic anisotropy and interface DMI. Moreover, due to the epitaxial growth of Co(0001) on W(110) following the Nishiyama Wasserman relationships, the circular symmetry is broken, giving rise into a C2v crystal symmetry at the Co/W(110) interface. This symmetry results into a biaxial magnetic anisotropy and into an anisotropic DMI . Consequently, the competition between both interactions lead to an anisotropic domain wall configuration as well as domain wall energy. This is confirmed experimentally by our X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) experiments.

In this talk, I will show how the strength of the different magnetic interactions can be tuned as function of the Au-to-Pt content, leading to different type of anisotropic topological textures such as elliptical skyrmions or merons