Non-equilibrium green's function fromalism combined with density functional theory is used to investigate the photogalvanic effect of chromium (Cr)-doped monolayer molybdenum disulfide (MoS₂) from first principles. Since the Cr-doped monolayer MoS₂ belongs to the C₂v point group which is non-inversion symmetric, the photocurrent can be generated at zero bias when irradiated by linearly or circularly polarized light. Then, the photoresponse for the circular photogalvanic effect (CPGE) and linear photogalvanic effec (LPGE) at different photon energies are investigated. It is found that the photoresponse of the CPGE is one order of magnitude larger than the LPGE and there are peaks around 1.5 eV, 1.9 eV and 2.0 eV for the CPGE. Especially, the photocurrent reaches the maximum value at the photon energy of 1.5 eV (red light) for the CPGE. These results can be explained by the electron transition between valence bands and conduction bands, which is proportional to density of states according to the Fermi's golden rule. Furthermore, we investigate the dependence of the photocurrent on polarization angle θ and φ for the LPGE and CPGE. Since the Cr-doped monolayer MoS₂ can generate a large photocurrent in the visible light range, it can be used as an excellent photogalvanic material. This work indicates that Cr-doped monolayer MoS₂ can provide some theoretical references for the research and design of novel electronic or optoelectronic devices.

非平衡格林函数的泛用论与密度泛函理论相结合，从第一原理出发研究了掺铬（Cr）单层二硫化钼（MoS ₂）的光电流效应。由于Cr掺杂的单层MoS ₂属于C ₂ v在非反转对称的点组中，当被线性或圆偏振光照射时，光电流可以在零偏压下产生。然后，研究了在不同光子能量下圆形光电效应（CPGE）和线性光电效应（LPGE）的光响应。发现CPGE的光响应比LPGE大一个数量级，并且CPGE在1.5eV，1.9eV和2.0eV附近存在峰值。特别是，对于CPGE，在1.5 eV（红光）的光子能量下，光电流达到最大值。这些结果可以用价带和导带之间的电子跃迁解释，根据费米黄金定律，电子跃迁与态密度成正比。此外，我们研究了光电流对极化角的依赖性LPGE和CPGE的θ和φ。由于掺杂Cr的单层MoS ₂可以在可见光范围内产生大的光电流，因此可以用作优良的光电流材料。这项工作表明，Cr掺杂的单层MoS ₂可以为新型电子或光电子器件的研究和设计提供一些理论参考。