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基于GeC和WS2超晶格的第一性原理研究
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Abstract:
本文通过第一性原理研究了GeC/WS2超晶格结构，利用密度泛函理论(DFT)和VASP软件包，详细分析了GeC和WS2单层材料的电子性质，并进一步探讨了GeC/WS2超晶格在六种不同堆叠方式下的原子结构和电子性质。计算结果显示六种堆叠结构均为II型能带排列的直接带隙半导体，带隙大小在0.55 eV到1.03 eV之间变化。这表明构建超晶格可以通过改变堆叠方式来调控超晶格的电子性质。此外，结合能和层间距的分析表明超晶格的物理稳定性与堆叠方式密切相关。这项研究不仅揭示了GeC/WS2超晶格在电子和光学性质调控方面的应用潜力，也为设计和制备具有特定功能的新型超晶格材料提供了理论基础。
In this paper, the GeC/WS2 superlattice structure is investigated by first principles, and the electronic properties of GeC and WS2 monolayers are analyzed in detail by using density-functional theory (DFT) and the VASP software package, and the atomic structure and electronic properties of the GeC/WS2 superlattice are further explored in six different stacking modes. The computational results show that all six stacked structures are direct bandgap semiconductors with type II energy band arrangement, and the bandgap size varies from 0.55 eV to 1.03 eV. This suggests that constructing superlattices can modulate the electronic properties of superlattices by changing the stacking method. In addition, the analysis of binding energy and layer spacing indicates that the physical stability of the superlattice is closely related to the stacking mode. This study not only reveals the potential application of GeC/WS2 superlattices in the modulation of electronic and optical properties, but also provides a theoretical basis for the design and preparation of novel superlattice materials with specific functions.
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