论文标题
在半导体异质上的频段偏移的有效和改进的预测来自meta-gga密度函数
Efficient and improved prediction of the band offsets at semiconductor heterojunctions from meta-GGA density functionals
论文作者
论文摘要
在半导体异质结构界面的频段取消频段的准确预测通常非常具有挑战性。尽管密度函数理论已经取得了合理的成功,以进行此类计算,并且需要有效,准确的半邻属功能来降低计算成本。通常,基于广义梯度近似(GGA)的半局部功能显着低估了散装带隙。反过来,这导致了异源界面处的频段偏移量的估计不准确。在本文中,我们研究了在半导体异质结的频段偏移的计算预测中,几个高级元gga功能的性能。 In particular, we investigate the performance of r2SCAN (revised strongly-constrained and appropriately-normed functional), rMGGAC (revised semilocal functional based on cuspless hydrogen model and Pauli kinetic energy density functional), mTASK (modified Aschebrock and Kümmel meta-GGA functional), and LMBJ (local modified Becke-Johnson) exchange-correlation functionals.我们的结果强烈表明,这些用于超级电池计算的元ggga功能表现良好,尤其是与计算上要求更高的GW计算相比。我们还提出了使用电离势和电子亲和力计算的带反量,以及通过分支点能的带对齐。总体而言,我们的研究表明,可以在DFT框架内使用上述元ggga功能,以估计具有预测精度的半导体异质结构中的频段偏移。
Accurate theoretical prediction of the band offsets at interfaces of semiconductor heterostructures can often be quite challenging. Although density functional theory has been reasonably successful to carry out such calculations and efficient and accurate semilocal functionals are desirable to reduce the computational cost. In general, the semilocal functionals based on the generalized gradient approximation (GGA) significantly underestimate the bulk band gaps. This, in turn, results in inaccurate estimates of the band offsets at the heterointerfaces. In this paper, we investigate the performance of several advanced meta-GGA functionals in the computational prediction of band offsets at semiconductor heterojunctions. In particular, we investigate the performance of r2SCAN (revised strongly-constrained and appropriately-normed functional), rMGGAC (revised semilocal functional based on cuspless hydrogen model and Pauli kinetic energy density functional), mTASK (modified Aschebrock and Kümmel meta-GGA functional), and LMBJ (local modified Becke-Johnson) exchange-correlation functionals. Our results strongly suggest that these meta-GGA functionals for supercell calculations perform quite well, especially, when compared to computationally more demanding GW calculations. We also present band offsets calculated using ionization potentials and electron affinities, as well as band alignment via the branch point energies. Overall, our study shows that the aforementioned meta-GGA functionals can be used within the DFT framework to estimate the band offsets in semiconductor heterostructures with predictive accuracy.