Depth-resolved investigations of interfacial effects in Fe-based layered magnetic nanostructures

Place: conference hall, IMDEA Nanociencia.

Abstract: 

The study of layered magnetic nanostructures and interface-induced phenomena are of fundamental relevance in physics and materials science, due to the importance for spintronics and related areas, and the potential for new applications and disruptive technologies. For such systems, the possibility of conducting depth-resolved measurements and accessing buried magnetic interfaces is of vital relevance but can be challenging. The combination of isotope-enriched probe layers and conversion electron Mössbauer spectroscopy (CEMS) can be a powerful tool for direct studies of the structural, chemical, and magnetic properties of surfaces and buried interfaces, allowing depth resolution inside a layer of the same chemical element.

In this talk, will be presented and discussed studies on the growth, structure, and magnetism of layered nanostructures (FM/AFM, FM/NM) prepared by molecular beam epitaxy and by sputtering. The potential offered by the application of isotope-selective measurements for the study of surfaces and interfaces will be illustrated with recent ⁵⁷Fe CEMS results on the investigation of depth-dependent spin structures, magnetization reversal, and interfacial interdiffusion in different Fe-based exchange-biased FM/AFM systems grown by sputtering (FeCo/IrMn, Fe/FeMn, FeCo/Mn₂Au,…) [1, 2]. For FM/NM systems, it will be discussed the influence of chemical order on the magnetic anisotropy of epitaxial Fe/Co ultrathin films on Cu₃Au(001), and the induced magnetization in the non-magnetic surface atoms, investigated by combining conventional surface-sensitive techniques, X-ray magnetic circular dichroism (XMCD) measurements, and depth-dependent first-principles calculations [3-5].

[1] L. E. Fernandez-Outon et al., J. Magn. Magn. Mater. 467, 139 (2018).

[2] L. E. Fernandez-Outon et al., J. Magn. Magn. Mater. 504, 166657 (2020).

[3] A. S. Ponce et al., AIP Advances 8, 115307 (2018). 

[4] S. O. Parreiras et al., Appl.  Surf.  Sci. 548, 149215 (2021).

[5] L. Cabral et al., Phys. Rev. B 106, 214430 (2022).