AI 中文总结
针对DFT带隙问题导致窄禁带半导体缺陷能级预测困难的问题，提出ba-occ-DFT方法，规避带隙问题并实现InAs缺陷能级的严格预测。
AI 中文摘要
密度泛函理论（DFT）低估了实验带隙，这就是著名的带隙问题。由于带隙决定了缺陷能级的能量尺度，这会使原子缺陷的电荷跃迁能量计算变得复杂。在窄禁带半导体的极端情况下，DFT带隙会坍缩为零，似乎无法对缺陷能级进行定量预测。我们提出了一种带隙规避的占据约束DFT（ba-occ-DFT）方法，该方法可防止带边态的虚假占据，并能可靠计算原子缺陷的总能。将其应用于砷化铟（InAs）表明，ba-occ-DFT可规避带隙问题，将带边误差与缺陷能级计算分离，尽管DFT带隙为零，仍能对窄禁带半导体中的缺陷能级进行严格预测。
英文摘要
Density functional theory (DFT) underestimates the experimental band gap---the infamous band gap problem. As the band gap defines the energy scale of defect levels, this complicates computation of charge transition energies for atomic defects. In the extreme case of narrow-gap semiconductors, the DFT band gap collapses to zero, seemingly precluding quantitative predictions of defect levels. We present a band-avoiding occupation-constrained DFT (ba-occ-DFT) approach that prevents spurious occupation of band-edge states and enables reliable total energy calculations of atomic defects. Application to indium arsenide (InAs) shows that ba-occ-DFT circumvents the band gap problem, separates band-edge errors from defect level calculations, and enables rigorous defect level predictions in a narrow-gap semiconductor despite a zero DFT band gap.
