The optical and electronic properties of pure graphene, nitrogen doped graphene, gallium doped graphene and nitrogen and gallium co-doped graphene were researched based on the first-principle method of density functional theory (DFT). Pure graphene has a zero-band structure, and when doped in graphene, its bands are opened. In this study, the bandgap of N-doped graphene was 0.20 eV, Ga-doped graphene was 0.35 eV and N–Ga co-doped graphene was 0.49 eV. They also have different electron density. In the N–Ga co-doped graphene, the N atom gained more electrons (−0.6 1e) than the N-doped graphene (−0.27 e), and the Ga atom lost more electrons (1.80 e) than the Ga-doped graphene (1.75 e). Moreover, the optical properties of pure graphene and doped graphene were analyzed and compared. These properties include complex refractive index, dielectric function and light absorption. From these analysis results, it can be seen that the doping study in graphene has effectively improved the optical and electrical properties of graphene. This study provides an effective theoretical foundation for the future development of graphene-based photoelectric devices.

中文翻译：

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(Ga,N,Ga-N)掺杂石墨烯的电子结构和光学性质的第一性原理计算研究

基于密度泛函理论（DFT）的第一性原理方法研究了纯石墨烯、氮掺杂石墨烯、镓掺杂石墨烯以及氮镓共掺杂石墨烯的光学和电子特性。纯石墨烯具有零能带结构，当掺杂在石墨烯中时，其能带打开。在本研究中，N掺杂石墨烯的带隙为0.20 eV，Ga掺杂石墨烯为0.35 eV，N-Ga共掺杂石墨烯为0.49 eV。它们还具有不同的电子密度。在N-Ga共掺杂石墨烯中，N原子比N掺杂石墨烯（-0.27 e）获得更多电子（-0.6 1e），Ga原子比Ga掺杂石墨烯失去更多电子（1.80 e） (1.75 e)。此外，对纯石墨烯和掺杂石墨烯的光学性质进行了分析和比较。这些特性包括复折射率、介电功能和光吸收。从这些分析结果可以看出，石墨烯中的掺杂研究有效地提高了石墨烯的光学和电学性能。该研究为石墨烯基光电器件的未来发展提供了有效的理论基础。