Enhanced Nonlinear Optical Response of Rectangular MoS₂ and MoS₂/TiO₂ in Dispersion and Film

The nonlinear response of the two-dimensional materials could be measured by the spatial self-phase modulation (SSPM) and Z scan. Most of these materials are irregular shapes. In this paper, we studied the nonlinear optical properties of rectangular layered MoS₂ and the corresponding MoS₂/TiO₂ composite in dispersion and the film, respectively. For dispersion measured by SSPM, the nonlinear refraction index of rectangular layered MoS₂ dispersion is larger than that of the MoS₂/TiO₂ composite dispersion. For film measured by Z scan, the nonlinear refractive index of the MoS₂/TiO₂ composite thin film is larger than that of the rectangular layered MoS₂ thin film. This research confirms the possibility of the nonlocal electron coherence established among the alignment in SSPM and provides two different paths for the enhancement of the nonlinear optical properties of MoS₂