Effect of annealing on the structure and magnetic properties of Co2FeAl0.5Si0.5 thin films on Ge(111)

DOI: 10.1016/j.jallcom.2018.03.075

Authors: Balati Kuerbanjiang (University of York) , Christopher Love (University of York; Diamond Light Source) , Demie Kepaptsoglou (SuperSTEM Laboratory) , Zlatko Nedelkoski (University of York) , Shinya Yamada (Osaka University) , Arsham Ghasemi (University of York) , Quentin M. Ramasse (SuperSTEM Laboratory) , Kohei Hamaya (Osaka University) , Stuart A. Cavill (University of York; Diamond Light Source) , Vlado K. Lazarov (University of York)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Alloys And Compounds

State: Published (Approved)
Published: March 2018

Abstract: We present a magnetic and structural properties study of epitaxially grown B2-ordered full Heusler Co2FeSi0.5Al0.5 single crystal films on Ge(111) substrates, as a function of annealing temperature. Hysteresis loop measurements reveal that the magnetic properties of Co2FeSi0.5Al0.5 are stable up to 450 °C while ferromagnetic resonance linewidth measurements show a reduction of Gilbert damping from 5.6 × 10−3 to 2.9 × 10−3 for as-grown and annealed film, respectively. Above 500 °C, the films have increased coercivity, decreased saturation magnetisation, and show characteristic two-magnon scattering resonance line-shapes. Magnetic inhomogeneities developed within the film when annealed above 500 °C were correlated to significant interdiffusion at the film-substrate interface, as confirmed by scanning transmission electron microscopy and electron energy loss spectroscopy. By performing first-principles calculations based on atomistic models developed from atomically-resolved microscopy images, we show the magnetic moment of the Co2FeSi0.5Al0.5 film reduces upon Co substitution by Ge atoms.

Diamond Keywords: Ferromagnetism

Subject Areas: Physics, Materials


Technical Areas:

Added On: 13/03/2018 11:27

Discipline Tags:

Surfaces Quantum Materials Physics Hard condensed matter - structures Magnetism Materials Science interfaces and thin films Metallurgy

Technical Tags: