A new stable antiferromagnetic semiconductor: The case of inverse Heusler compound Ti2CrSn. (June 2017)

• Record Type: Journal Article
• Authors: Li, Jia; Zhang, Qiang; Li, Jie; Yang, Guang; Ma, Hongran; Zhou, Guoxiang; Lu, Zunming; Fang, Wei; Xie, Hongxian; Liang, Chunyong; Yin, Fuxing
• Is Part Of: Intermetallics. Volume 85(2017)
• Page Start: 149
• Page End: 155
• Publication Date: 2017-06
• Subjects: Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2017.02.013
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: The inverse Heusler compound Ti 2 CrSn with L 2 1 phase is predicted to be antiferromagnetic semiconductor with an indirect gap of 0.2 eV based on first principles and Boltzmann transport theory. The semiconducting character is stable within a large strain from −6% to 6%. The Cr, Ti 1 and Ti 2 moments all show a linear change behavior within the strain range of −6% ∼ 6%, however, the total zero moment is robust within that strain range. It should be a potential candidate for applying to magnetic tunnel junction device. The total zero moment originates from the fully occupied 9 orbitals for both up and down spin directions below the Fermi level. The spin dependent 3d hybridization feature is found that for up spin states the hybridization between Cr and Ti 2 is dominant while for down spin states the hybridization between Ti 1 and Ti 2 is dominant, however, there is no clear indication of hybridization between Cr and Ti 1 . The gap origin of the spin up (down) direction is that the 3d hybridization of Cr − Ti 2 ( Ti 1 − Ti 2 ) forms the bonding three degenerate t 2 g as well as two degenerate e g below the Fermi level, and also corresponding antibonding states of them above the Fermi level. This hybridization character also can be seen from the electron density difference that only the region between Cr and Ti 2, and between Ti 1 and Ti 2 show clear electrons accumulation suggesting strong interaction. The calculated value of thermoelectric power factor is near to that of Bi 2 Te 3, marking its potential application values in thermoelectric field. Highlights: A new antiferromagnetic semiconductor, the inverse Heusler compound Ti2 CrSn, has been predicted. A spin dependent 3d hybridization mechanism in forming the electronic band structure of Ti2 CrSn has been found. It should be a good candidate for applying to magnetic tunnel junction or thermoelectric device.