Ab initio exploration of d(0) digital magnetic heterostructures: the case of MgO and CaO delta-doped with potassium

作者：Du, Jiangtao; Dong, Shengjie; Lu, Yi-Lin; Zhao, Hui; Wang, Liying; Feng, Liefeng^*

来源：European Physical Journal B, 2017, 90(6): 118.

DOI：10.1140/epjb/e2017-70495-y

• HALF-METALLIC FERROMAGNETISM
• GENERALIZED GRADIENT APPROXIMATION
• ROOM-TEMPERATURE FERROMAGNETISM
• DENSITY-FUNCTIONAL THEORY
• ELECTRONIC-STRUCTURE
• CSCL STRUCTURE
• 1ST-PRINCIPLES
• ALLOYS
• SUPERLATTICES
• GAAS/MN

Previous studies of digital magnetic heterostructures have mainly focused on 3d transition metal delta-doped semiconductors. In this work, sp-electron digital magnetic heterostructures without magnetic ions are proposed. Based on a theoretical density functional investigation, electronic structures and magnetic properties of MgO and CaO delta-doped with K were reported. The results show that these heterostructures are half-metallic ferromagnetic materials having semiconducting up spins and metallic down spins, with an exchange interaction much stronger than that of a random alloy with similar K concentration. Our first-principles calculations show that the carriers at the Fermi level are strongly confined within a few monolayers around the KO plane. This strong confinement is responsible for the large exchange coupling and the two-dimensional half-metallic behavior. The thickness of the host semiconducting spacer does not significantly change the global electric and magnetic features.

• 出版日期2017-6-21
• 单位天津师范大学; 天津大学