School of Information Science and Engineering, Shandong University, Jinan 250100, China.
Nanoscale Res Lett. 2014 Oct 18;9(1):580. doi: 10.1186/1556-276X-9-580. eCollection 2014.
First-principles calculations based on density functional theory have been performed for the quaternary GaAs1-x-y N x Bi y alloy lattice-matched to GaAs. Using the state-of-the-art computational method with the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, electronic, and optical properties were obtained, including band structures, density of states (DOSs), dielectric function, absorption coefficient, refractive index, energy loss function, and reflectivity. It is found that the lattice constant of GaAs1-x-y N x Bi y alloy with y/x =1.718 can match to GaAs. With the incorporation of N and Bi into GaAs, the band gap of GaAs1-x-y N x Bi y becomes small and remains direct. The calculated optical properties indicate that GaAs1-x-y N x Bi y has higher optical efficiency as it has less energy loss than GaAs. In addition, it is also found that the electronic and optical properties of GaAs1-x-y N x Bi y alloy can be further controlled by tuning the N and Bi compositions in this alloy. These results suggest promising applications of GaAs1-x-y N x Bi y quaternary alloys in optoelectronic devices.
基于密度泛函理论的第一性原理计算已经针对与 GaAs 晶格匹配的四元 GaAs1-x-y N x Bi y 合金进行了研究。使用具有 Heyd-Scuseria-Ernzerhof（HSE）杂化泛函的最先进计算方法，获得了电子和光学性质，包括能带结构、态密度（DOS）、介电函数、吸收系数、折射率、能量损失函数和反射率。结果发现，y/x =1.718 的 GaAs1-x-y N x Bi y 合金的晶格常数可以与 GaAs 匹配。通过将 N 和 Bi 掺入 GaAs 中，GaAs1-x-y N x Bi y 的能带隙变小并保持直接带隙。计算的光学性质表明，GaAs1-x-y N x Bi y 的光学效率更高，因为它的能量损失比 GaAs 少。此外，还发现通过调整这种合金中的 N 和 Bi 组成，可以进一步控制 GaAs1-x-y N x Bi y 合金的电子和光学性质。这些结果表明 GaAs1-x-y N x Bi y 四元合金在光电器件中有很有前途的应用。
