Author:
Shan Wanfei,Du Jiangtao,Luo Weidong
Abstract
Lattice superlattices constructed with different materials such as ferromagnets and insulators at atomic scale provide an ideal platform for exploring many emergent physical phenomena. In the present work, a new type of superlattices composed of ferromagnetic half-metal CrO2, with a thickness of two atomic layers, together with insulating MgH2 are constructed. Systematic theoretical studies on the (CrO2)2/(MgH2)
n
(n = 2, 3, 4, 5, 6) superlattices are carried out based on first-principles density-functional theory calculations. These superlattices are ferromagnetic semiconductors with similar intra-layer magnetic exchange couplings between Cr ions. As the thickness of the MgH2 layer increases, the magnetic exchange interaction between inter-layer Cr ions shows oscillating decaying behavior, while the energy band gaps show a small increase. The understanding of magnetic couplings in these superlattices provides a pathway for constructing new ferromagnetic semiconductors.
Subject
General Physics and Astronomy