Two-dimensional diamane-like [formula omitted] and [formula omitted]: Wide bandgap and bipolar magnetic semiconductors

Abstract

Two-dimensional bipolar magnetic semiconductors demonstrate great application potential in developing novelty spintronic devices. Here, we explore the electronic and magnetic characteristics of diamane-like structures Si2C(Ge)2H2 and Si2C(Ge)2H based on the first-principles calculations. The results uncover that Si2C(Ge)2H2 are wide bandgap semiconductors and Si2C(Ge)2H are bipolar magnetic semiconductors. Further calculations demonstrate the flexible magnetic structures for Si2C2H-I, Si2C2H-II, Si2Ge2H-I and Si2Ge2H-II based on the external strain field. Significantly, the magnetic type transforming from bipolar magnetic semiconductor to half semiconductor happens when appropriate strain is applied on the structure with a narrow spin-conserved energy gap. Our work enrich the diversity of 2D magnetic semiconductors and put forward a series of materials for the candidates of spintronic applications.