Abstract In the recent decade, extensive efforts have been made to find new two-dimensional (2D) materials. Theatrical studies can offer promising stable candidates for experimental peers to explore. In this study, the structural stability, electrical and optical properties of 2D tetragonal MgX (X = S, Se) monolayers were systematically investigated by using density functional theory (DFT). Based on our computation, 2D tetragonal MgS and MgSe monolayers indicate very good thermodynamic and kinetic stabilities which suggest their promising to be experimentally realized. The results demonstrated that 2D MgS and MgSe are indirect semiconductors showing strain tunable wide band gaps (WBG). Furthermore, analyzing the optical aspects of these 2D materials suggested their potential applicable characteristics for using in UV applications. As WBG semiconductors, 2D monolayer MgS and MgSe may have promising applications in electro-optical devices in nano-scale.

中文翻译：

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二维四方 MgX (X=S, Se) 单层半导体的应变可调电学和光学性质

摘要 近十年来，人们为寻找新的二维 (2D) 材料做出了广泛的努力。戏剧研究可以为实验同行提供有前途的稳定候选者进行探索。在这项研究中，使用密度泛函理论 (DFT) 系统地研究了二维四方 MgX (X = S, Se) 单层的结构稳定性、电学和光学性质。根据我们的计算，二维四方 MgS 和 MgSe 单层显示出非常好的热力学和动力学稳定性，这表明它们有望通过实验实现。结果表明，2D MgS 和 MgSe 是显示应变可调宽带隙 (WBG) 的间接半导体。此外，对这些 2D 材料的光学方面的分析表明它们在紫外线应用中的潜在适用特性。