Substrate dependent reduction of Gilbert damping in annealed Heusler alloy thin films grown on group IV semiconductors

DOI: 10.1063/5.0060213

Authors: C. J. Love (University of York; Diamond Light Source) , B. Kuerbanjiang (University of York) , A. Kerrigan (University of York) , S. Yamada (Osaka University) , K. Hamaya (Osaka University) , G. Van Der Laan (Diamond Light Source) , V. K. Lazarov (University of York) , S. A. Cavill (University of York)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Applied Physics Letters , VOL 119

State: Published (Approved)
Published: October 2021

Abstract: A structural and FMR study is presented for epitaxial thin films of the Heusler alloy Co2FeAl0.5Si0.5 (CFAS) grown on Ge(111) and Si(111) substrates. All films, as-grown and post-annealed, show B2 ordering; full chemical order (L21) is not obtained over the range of anneal temperatures used in this study. As-grown films show a lower Gilbert damping constant, α, when grown on a Si(111) substrate compared to Ge(111). Annealing the films to 450 °C significantly reduces α for CFAS on Ge while increasing α for CFAS on Si. This is related to a substrate dependent competition between improvements in lattice structure and increased interfacial intermixing as a function of anneal temperature. The optimal annealing temperature to minimize α is found to differ by ∼100 K between the two substrates. Above an anneal temperature of 500 °C, films grown on both substrates have increased coercivity, decreased saturation magnetization, and show characteristic two-magnon scattering features.

Journal Keywords: Magnetic materials; Annealing; Thin films; Epitaxy; Semiconductors; Alloys; Spintronics; Magnetization dynamics

Diamond Keywords: Alloys; Spintronics; Ferromagnetism; Semiconductors

Subject Areas: Materials, Physics


Technical Areas:

Added On: 01/11/2021 09:20

Documents:
5.0060213.pdf

Discipline Tags:

Surfaces Quantum Materials Physics Electronics Magnetism Materials Science interfaces and thin films Metallurgy

Technical Tags: