铝掺杂及应变对单层黑磷电子性质作用的计算研究

Computational Study on the Effects of Aluminum Doping and Strain on Electronic Properties of Monolayer Black Phosphorus

摘要: 文章采用第一性原理密度泛函理论，探究本征单层黑磷及双轴应变下铝掺杂单层黑磷的电子结构与光学性能。研究发现，铝掺杂会使带隙变窄，且带隙宽度会随着压缩应变的增大而减小，随着拉伸应变的增大带隙先增大后减小。此外，铝掺杂单层黑磷的静态介电常数会随着拉应变的增大而降低，在压应变条件下呈现出显著的上升趋势。在红外波段和可见光波段范围内，该掺杂体系介电函数的虚部会随压应变的增大而增大。当施加压应变时，其吸收峰向低能方向移动(红移)；而施加拉应变时，其吸收峰降低并发生蓝移。上述特性使铝掺杂单层黑磷成为一种极具潜力的候选材料，可用于制备利用其应变可调特性的先进电子与光学器件。

Abstract: This study employs first-principles density functional theory to investigate the electronic structure and optical properties of intrinsic monolayer black phosphorus and aluminum-doped monolayer black phosphorus under biaxial strain. The findings reveal that aluminum doping narrows the bandgap, and the bandgap width decreases with increasing compressive strain; under tensile strain, the bandgap first increases and then decreases. Furthermore, the static dielectric constant of aluminum-doped monolayer black phosphorus decreases with increasing tensile strain and exhibits a significant upward trend under compressive strain. In the infrared and visible light regions, the imaginary part of the dielectric function of this doped system increases with increasing compressive strain. When compressive strain is applied, the absorption peak shifts toward lower energies (red shift); conversely, when tensile strain is applied, the absorption peak decreases and undergoes a blue shift. These characteristics make aluminum-doped monolayer black phosphorus a highly promising candidate material for the fabrication of advanced electronic and optical devices that leverage its strain-tunable properties.