Kaur Sumandeep, Kumar Ashok, Srivastava Sunita, Tankeshwar K
Department of Physics, Panjab University, Chandigarh 160014, India.
Phys Chem Chem Phys. 2016 Jul 21;18(27):18312-22. doi: 10.1039/c6cp01252c. Epub 2016 Jun 23.
We report the tailoring of the electronic structures of various structural phases of phosphorene (α-P, β-P, γ-P and δ-P) based homo- and hetero-bilayers through in-plane mechanical strains, vertical pressure and transverse electric field by employing density functional theory. In-plane biaxial strains have considerably modified the electronic bandgap of both homo- and hetero-bilayers while vertical pressure induces metallization in the considered structures. The γ-P homo-bilayer structure showed the highest ultimate tensile strength (UTS ∼ 6.21 GPa) upon in-plane stretching. Upon application of a transverse electric field, the variation in the bandgap of hetero-bilayers was found to be strongly dependent on the polarity of the applied field which is attributed to the counterbalance between the external electric field and the internal field induced by different structural phases and heterogeneity in the arrangements of atoms of each surface of the hetero-bilayer system. Our results demonstrate that the electronic structures of the considered hetero- and homo-bilayers of phosphorene could be modified by biaxial strain, pressure and electric field to achieve the desired properties for future nano-electronic devices.
我们通过采用密度泛函理论，报告了通过面内机械应变、垂直压力和横向电场对磷烯（α-P、β-P、γ-P和δ-P）各种结构相的同质和异质双层的电子结构进行剪裁的情况。面内双轴应变显著改变了同质和异质双层的电子带隙，而垂直压力在所考虑的结构中诱导了金属化。γ-P同质双层结构在面内拉伸时表现出最高的极限抗拉强度（UTS ∼ 6.21 GPa）。在施加横向电场时，发现异质双层带隙的变化强烈依赖于所施加电场的极性，这归因于外部电场与由不同结构相以及异质双层系统每个表面原子排列的不均匀性所诱导的内场之间的平衡。我们的结果表明，通过双轴应变、压力和电场可以改变所考虑的磷烯异质和同质双层的电子结构，以实现未来纳米电子器件所需的性能。
