Applied Surface Science, Vol.475, 839-846, 2019
Tuning electronic properties of InSe/arsenene heterostructure by external electric field and uniaxial strain
First-principles based on density functional theory (DFT) are used to calculate the structural and electronic properties of InSe/arsenene heterostructure. The results show that the InSe/arsenene bilayer forms a type-II van der Waals heterostructure with a direct band gap of 0.876 eV, which is favorable for the separation of photo-generated electron-hole pairs. The properties of InSe/arsenene heterojunction can be effectively regulated by applying an external electric field and uniaxial strain. When an external electric field is applied, the heterostructure experiences a transition from semiconductor to metal. In addition, due to the presence of built-in electric field, the positive and negative electric fields have different effects on the electronic properties of heterostructure. When uniaxial strain is applied, the heterostructure can withstand larger tensile strain than compression strain without damaging the structure and the band gap is more easily decreased by X-direction strain. In addition, the heterostructure undergoes a direct-indirect bandgap transition under strain. When compressive strain is applied in the Y direction, especially epsilon < - 2%, the heterostructure possesses a higher carrier mobility while maintaining direct bandgap characteristics. Our results show that the new InSe/arsenene heterostructure has great potential for applications in electronic and optoelectronic devices.