title: Strong current polarization and perfect negative differential resistance in few-FeN4-embedded zigzag graphene nanoribbons.
abstract: Ferromagnetic devices have special significance in spintronics. Here, we investigate the electronic structures and transport properties of the experimentally achievable FeN4-embedded armchair and zigzag graphene nanoribbons (FeN4-AGNR and FeN4-ZGNR). The first principles results show that FeN4induces room-temperature stable ferromagnetic ground states in both AGNRs and ZGNRs, but only significant changes in the band structure of the latter, inducing strong current polarization (nearly 100%) and spin-dependent negative differential resistance (NDR) in the FeN4-ZGNR based devices. We find that the performance of the NDR can be easily enhanced by embedding more FeN4structures. Its peak-to-valley current ratio (PVCR) rises rapidly and reaches 104when only 4 FeN4structures are used. It is revealed that the localized f electrons of the Fe atom and the p electrons of the C atoms at the ribbon edges have the same spin orientation, resulting in a ferromagnetic ground state with a larger magnetic moment, FeN4induces conductive states around the Fermi level, which are responsible for the observed NDR, and the quite different conductivity of the frontier orbitals in the spin-down and spin-down systems contributes to the strong current polarization. Such intrinsic properties suggest prospective device applications of the FeN4-ZGNRs in spintronics.
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Xiao-Fei
authors.identifier: http://orcid.org/0000-0002-0851-3885
authors.initials: XF
authors.lastname: Li
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Lingling
authors.initials: L
authors.lastname: Liu
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yan
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Qin-Kun
authors.initials: QK
authors.lastname: Li
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Yunxiang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Guizhou Synergetic Innovation Center of Scientific Big Data for Advanced Manufacturing Technology, Guizhou Education University, Guiyang, 550018, China.
authors.forename: Mingsen
authors.initials: M
authors.lastname: Deng
authors.affiliation: School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. xf.li@uestc.edu.cn.
authors.forename: Qi
authors.initials: Q
authors.lastname: Qiu