The 66th JSAP Spring Meeting, 2019

Presentation information

Oral presentation

10 Spintronics and Magnetics » 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

[9p-M101-1~7] 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

Sat. Mar 9, 2019 4:00 PM - 6:00 PM M101 (H101)

Hiromi Yuasa(Kyushu univ.)

4:00 PM - 4:15 PM

[9p-M101-1] Ab-initio search for half-metal Co-based full Heusler alloy

Kenji Nawa1, Yoshio Miura1 (1.NIMS)

Keywords:Co-based Heusler alloy, Half-metal, Density functional theory

Co-based full Heusler alloy is a key material due to a high Curie temperature and a possibility to show half-metallic ferromagnetism (HMF). The ab-initio calculations have been expected to play a great role in search of HM materials, but most of theoretical studies have a lack of electron correlation effect while this interaction is essential to understand physical property of Heusler alloys.
In this study, the DFT+U calculations, in which the correlation term U is determined theoretically, were performed to reinvestigate fundamental electronic structure of Co-based full Heusler alloys in bulk and to explore a capability of the HMF. For Co2MnSi, our calculations revealed the correlation effect of Mn is more significant than that of Co to obtain the electronic and magnetic structures where in good agreement with experiments. Then the DFT+U calculations including only Mn-correlation concluded the HMF is appeared in Co2MnSi. Furthermore, in quaternary system, we found the most promising candidates for HMF materials are the Co2(Ti0.25,Mn0.75)Si and Co2(Fe0.25,Mn0.75)Si in terms of the Fermi energy locating at around the center of conduction and valence states.