Magnetic damping constant in Co-based full heusler alloy epitaxial films. (29th April 2015)

• Record Type: Journal Article
• Authors: Oogane, M; Kubota, T; Naganuma, H; Ando, Y
• Is Part Of: Journal of physics. Volume 48:Number 16(2015)
• Page Start: 2152
• Publication Date: 2015-04-29
• Subjects: Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/48/16/164012
• Languages: English
• ISSNs: 0022-3727

Abstract

<abstract> <title>Abstract</title> <p>Co-based full-Heusler alloys, such as Co₂MnSi and Co₂MnGe, are expected to be used as half-metallic ferromagnetic material, which has complete spin polarization. They are the most promising materials for realizing half-metallicity at room temperature due to their high Curie temperature. The optimization of the magnetic damping constant of ferromagnetic materials is extremely important for achieving high-speed magnetization switching and reducing critical current density for spin torque transfer switching. We have systematically investigated the magnetic damping constant in Co-based full Heusler alloy epitaxial films. We found that the Gilbert damping constant seems to be roughly proportional to the total density of states at the Fermi level (<italic>E</italic>_{<italic>F</italic>}) by first principle calculation. A very small magnetic damping constant of 0.003 in the Co₂F_e0.4Mn_0.6Si epitaxial film was demonstrated. The small magnetic damping constant in Co₂Fe_{<italic>x</italic>}Mn_{1−<italic>x</italic>}Si films with <italic>x</italic> &lt; 0.6 can be attributed to the half-metallicity of Heusler alloys. Co-based full Heusler alloys with both half-metallicity and small magnetic damping will be very useful for future applications based on spintronic devices.</p> </abstract>