论文标题
激子在单晶α-SNS中的各向异性行为
Anisotropic Behavior of Excitons in Single Crystal α-SnS
论文作者
论文摘要
我们通过考虑原子轨道在分析上研究了基本吸收边缘附近的单晶α-SNS的各向异性介电特性。最引人注目的是扶手椅（B-）轴方向的激子特征，在低温下，这特别突出。为了确定这种各向异性的起源，我们使用包括电子孔相互作用的GW0 Bethe-Salpeter方程（BSE）执行第一原理计算。结果表明，各向异性介电特性是P轨道天然各向异性的直接结果。特别是，这种主要的激子特征源自γ-Y区域的马鞍点的PY轨道。
We investigate analytically the anisotropic dielectric properties of single crystal α-SnS near the fundamental absorption edge by considering atomic orbitals. Most striking is the excitonic feature in the armchair- (b-) axis direction, which is particularly prominent at low temperatures. To determine the origin of this anisotropy, we perform first-principles calculations using the GW0 Bethe-Salpeter equation (BSE) including the electron-hole interaction. The results show that the anisotropic dielectric characteristics are a direct result of the natural anisotropy of p orbitals. In particular, this dominant excitonic feature originates from the py orbital at the saddle point in the Γ-Y region.
