Nowadays, two-dimensional materials are ideal for fabricating optoelectronic and spintronic devices. We have investigated the optical and magnetic properties of −6 % to 6 % strain on Mn-adsorbed monolayer SnSe films using a first-principles approach. The Mn-adsorbed monolayer SnSe is a magnetic semiconductor in the absence of strain effects. As the tensile strain increases, the band gap of the Mn-adsorbed monolayer SnSe decreases and the structure becomes unstable, and Mn adsorption changes to exothermic adsorption at −6 % strain. The magnetic moment of the system increases slightly with increasing tensile strain and decreases rapidly when the strain reaches 4%. As the compressive strain increases, the magnetic moment first decreases slightly and then decreases rapidly when the strain reaches −4 %. Calculations of the optical properties show that the static dielectric constants at −6 %, −4 %, −2 %, 0 %, 2 %, 4 % and 6 % strains are 15.23, 10.19, 8.67, 7.78, 6.38, 5.99 and 5.92, respectively, which increase with increasing compressive strain. It decreases with increase in tensile strain. The static dielectric function increases as the compressive strain increases and decreases as the tensile strain increases. In the visible light region, the reflectivity, refractive index, extinction coefficient and photoconductivity in the XX and ZZ directions increase with increasing tensile strain. Our study shows that the optoelectronic and magnetic properties of the SnSe adsorbed Mn system can be improved to some extent by applying strain, and this study is expected to provide theoretical guidance for the fabrication of SnSe-based magnetic optoelectronic devices.

中文翻译：

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第一性原理计算研究应变对 Mn 吸附 SnSe2 单层磁和光学性质的影响

如今，二维材料是制造光电和自旋电子器件的理想选择。我们使用第一原理方法研究了 Mn 吸附单层 SnSe 薄膜在 -6% 至 6% 应变下的光学和磁学特性。在没有应变效应的情况下，吸附Mn的单层SnSe是一种磁性半导体。随着拉伸应变的增加，吸附Mn的单层SnSe的带隙减小，结构变得不稳定，并且在-6%应变时Mn吸附转变为放热吸附。系统的磁矩随着拉应变的增加而略有增加，当应变达到4%时迅速减小。随着压缩应变的增加，磁矩首先略有下降，然后当应变达到-4%时迅速下降。光学性能计算表明-6%、-4%、-2%、0%、2%、4%和6%应变下的静态介电常数分别为15.23、10.19、8.67、7.78、6.38、5.99和5.92 ，分别随着压缩应变的增加而增加。它随着拉伸应变的增加而减小。静态介电函数随着压缩应变的增加而增加，并随着拉伸应变的增加而减少。在可见光区域，XX和ZZ方向的反射率、折射率、消光系数和光电导率随着拉伸应变的增加而增加。我们的研究表明，通过施加应变可以在一定程度上改善SnSe吸附Mn体系的光电和磁性能，该研究有望为SnSe基磁光电器件的制造提供理论指导。