平面应变对二维单层氮化镓电子性质的调控作用

Tunable Electronic Properties of Two-Dimensional Gallium Nitride by In-plane Strain

采用第一性原理方法研究了二维单原子层氮化镓结构和电子性质的平面对称应变效应.结果表明,在-10%~10%的应变范围内,二维氮化镓的结构未遭到破坏,仍然保持稳定.通过对应变下的能带结构分析,发现随着拉应变的增大,二维氮化镓的带隙逐渐减小,而且保持间接带隙性质.在一定压应变作用下,二维氮化镓的带隙增大,由间接带隙转变为直接带隙.这表明平面对称应变可以有效地调节二维氮化镓的电子性质,为二维氮化镓的应用提供了有价值的理论依据.

The st ructural and elec t ronic proper t ies of two-dimensional hexagonal gal l ium ni t r ide under the in-plane st rain have been studied using the first principles methods. It is found that the st ructure of 2D h- GaN is stable under -10% ？10% s tra in . Based on the band st ructure calculations , it is found that the band gap decreases under tensi le st rain and keeps indirect . However, the band gap increases and becomes direct under certain compressive strain. These results indicate that the elect ronic propert ies of 2D h-GaN can be ef fect ively modulated by in-plane st rain, of fering an ef fect ive method for designing nanoscale tunable ul tra-thin optoelect ronic devices.