Structural and magnetic characterization of Fe/Cr/Fe tri‐layers and Fe/Cr multilayers after swift Au ion irradiation

Abstract

Fe/Cr/Fe trilayers and Fe/Cr multilayers were irradiated by 163 MeV Au ions with fluence of 1 × 1011 ions/cm2 to 50 × 1011 ions/cm2. The structural properties of Fe/Cr interfaces were observed using Conversion Electron Mössbauer Spectroscopy (CEMS) and X‐ray reflectivity (XRR). The magnetic exchange coupling between Fe layers through Cr spacer in trilayers and multilayers was determined from hysteresis loops measured with SQUID magnetometer. The different behavior of Fe/Cr/Fe trilayers and Fe/Cr multilayers was observed after Au ions irradiation. In Fe/Cr multilayers a decrease of the average value of hyperfine magnetic field with increasing Au ions fluence was observed, indicating an increase of the inter‐ increase of the interfacial roughness. In Fe/Cr/Fe trilayers the non‐monotonic behavior of average value of hyperfine magnetic field versus ion fluence was observed suggesting the smoothing of the interfaces at small fluences and roughening at higher ones. The smoothening of interfaces was confirmed by XRR spectra. In multilayers the magnetic properties changed in a similar way as the structural properties and continuous decay of antiferromagnetic coupling as a function of fluence was observed. In trilayers at the low fluences the antiferromagnetic coupling was not sensitive on irradiation, while at large fluences the decrease of antiferromagnetic coupling fraction was seen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Acceleration of volume decomposition of supersaturated Al + 4 wt.% Cu solid solution under irradiation with Ar+ ions

“…In the last decades, serious attention has been given to the problem of ion beam modification of surfaces of structural materials . In investigating the physical processes of interaction between accelerated ions and a solid, the principal attention was initially concentrated on a thin surface layer of a target comparable in its thickness with the projected range of the implanted ions.…”