B4CN3 and B3CN4 monolayers as the promising candidates for metal-free spintronic materials. (9th September 2016)

• Record Type: Journal Article
• Authors: Pan, Hongzhe; Sun, Yuanyuan; Zheng, Yongping; Tang, Nujiang; Du, Youwei
• Is Part Of: New journal of physics. Volume 18:Number 9(2016:Sep.)
• Publication Date: 2016-09-09
• Subjects: boron carbonitride -- spin gapless semiconductor -- bipolar magnetic semiconductor -- first-principle calculations; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/18/9/093021
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: The search for candidates of spintronic materials, especially among the two-dimensional (2D) materials, has attracted tremendous attentions over the past decades. By using a particle swarm optimization structure searching method combined with density functional calculations, two kinds of boron carbonitride monolayer structures (B4 CN3 and B3 CN4 ) are proposed and confirmed to be dynamically and kinetically stable. Intriguingly, we demonstrate that the magnetic ground states of the two B x C y N z systems are ferromagnetic ordering with a high Curie temperature of respectively 337 K for B4 CN3 and 309 K for B3 CN4 . Furthermore, based on their respective band structures, the B4 CN3 is found to be a bipolar magnetic semiconductor (BMS), while the B3 CN4 is identified to be a type of spin gapless semiconductor (SGS), both of which are potential spintronic materials. In particular, carrier doping in the B4 CN3 can induce a transition from BMS to half-metal, and its spin polarization direction is switchable depending on the doped carrier type. The BMS property of B4 CN3 is very robust under an external strain or even a strong electric field. By contrast, as a SGS, the electronic structure of B3 CN4 is relatively sensitive to external influences. Our findings successfully disclose two promising materials toward 2D metal-free spintronic applications.