In the rapidly evolving field of 2D materials, transition metal dichalcogenides (TMDs) have emerged as compelling candidates for electronic applications. This study investigates the electronic structure of the H-phase monolayer VS belonging to TMD family and the influence of strain on its band structure through Density Functional Theory (DFT). We employ two different pseudopotential approximations and a suite of computational methods including DFT+U, GAUPBE, G0W0, and self-GW to provide a nuanced understanding of its electronic band structure. A highlight of the study is its focus on how both uniaxial and biaxial strains, ranging from -5% to +5%, affect the electronic properties of the H-phase monolayer VS. Our comprehensive analysis reveals that these tensile strains significantly widen the energy gap, with uniaxial strains having a more pronounced effect than their biaxial counterparts. Additionally, we identify an intriguing phase transition from a semiconducting to a metallic state under compressive strains, this transition is attributed to both symmetry breaking and bond length variation in the uniaxial case, the bond length in biaxial. These key findings not only enrich our understanding of the intricate electronic behavior of monolayer VS under different strains but also pave the way for the design of innovative electronic devices using strain engineering.

中文翻译：

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单轴和双轴应变单层 VS 中的电子相变和能隙变化[公式省略] TMD：全面的 DFT 和超越 DFT 研究

在快速发展的二维材料领域，过渡金属二硫属化物 (TMD) 已成为电子应用领域引人注目的候选者。本研究通过密度泛函理论（DFT）研究了TMD族H相单层VS的电子结构以及应变对其能带结构的影响。我们采用两种不同的赝势近似和一套计算方法（包括 DFT+U、GAUPBE、G0W0 和 self-GW）来提供对其电子能带结构的细致入微的理解。该研究的一个亮点是重点关注单轴和双轴应变（-5% 至 +5%）如何影响 H 相单层 VS 的电子特性。我们的综合分析表明，这些拉伸应变显着扩大了能隙，单轴应变比双轴应变具有更明显的影响。此外，我们发现了在压缩应变下从半导体态到金属态的有趣相变，这种转变归因于单轴情况下的对称性破坏和键长变化，双轴情况下的键长。这些关键发现不仅丰富了我们对单层VS在不同应变下复杂电子行为的理解，而且为利用应变工程设计创新电子器件铺平了道路。