The nonlinear optical properties of the nanohybrid thin film forming by intercalating methylene blue dye into layered titanate nanosheets

Solid-state dye-doped materials are an attractive alternative to conventional liquid dye solution. In this study, the spectral characteristics and the nonlinear optical properties of dye methylene blue before and after intercalating into layered titanate nanosheets and forming a nanohybrid thin film were investigated by measuring the absorption and fluorescence spectra and using single beam z-scan technique under irradiation of low power continuous wave (CW) produced by He-Ne laser with a wavelength of 632.8 nm and DPSS laser with a wavelength of 532 nm, respectively. The nonlinear experimental results show that the MB/HTO nanohybrid thin film has a negative nonlinear refractive index under irradiation by He-Ne laser, but it reverses to positive value by DPSS laser.