Features of the Asperomagnetic Ordering of Thin Films of Heavy Rare-Earth Metals and Their Alloys With Co

This work is a comprehensive study of the magnetic properties of RE-Co films during the transition from a nanocrystalline state to an amorphous one. The concentration dependences of various magnetic parameters obtained in this work can be of great fundamental interest as well as applied significance, in connection with the use of these structures in various nanospintronic devices. To achieve the set goals, thin films of the RE<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">100-x</sub>C<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ox</sub> type (RE=Tb,Dy,Ho) were considered in the region of high concentrations of rare earth elements (0≤x≤50), characterized by the absence of a direct contribution of the Co subsystem to the spontaneous magnetization of binary compositions. The concentration dependences of the Curie temperature, coercive field, and average magnetic moment per atom of rare earth elements were determined. Taken together, the obtained results allow us to conclude that in the formation of the asperomagnetic state, which is realized in all the studied samples, an important role is played not only by the dispersion of the local anisotropy of rare-earth ions, but also and mostly by the exchange frustration of their magnetic moments caused by fluctuations of interatomic distances within the amorphized structure. In addition, it was concluded that there are two opposite trends in the concentration change in the magnetic properties of films, which are associated, on the one hand, with the amorphization of the structure and an increase in the indicated frustration, and, on the other hand, with the polarizing effect of the cobalt component caused by the hybridization of the electronic structures of rare earth and cobalt subsystem.