Effect of doping on the photogalvanic effect in monolayer MoSSe nanoribbons

Using a first-principles theoretical approach based on the non-equilibrium Green’s function formalism of density functional theory, we have investigated the linear photogalvanic effect and circular photogalvanic effect in monolayer MoSSe nanoribbons under different doping cases: pure MoSSe, Se-vacancy (VSe), S-vacancy (VSe), SSe-transposed (TSSe), Se-substituted S (SeS), and S-substituted Se (SSe). Our results demonstrate that doping reduces the spatial inversion symmetry of monolayer MoSSe, resulting in a significant increase in the photocurrent of the doped system and higher polarization sensitivity. Furthermore, we observed that the armchair direction exhibits a significantly stronger response to linearly polarized light than the zigzag direction, which is more sensitive to circularly polarized light. These findings indicate the wide range of promising applications of 2D MoSSe monolayers, such as in photodetection.