Nonlinear optical response spatial self-phase modulation in MoTe2: correlations between chi((3)) and mobility or effective mass

摘要

We report on an unambiguous observation of the third-order nonlinear optical effect, spatial self-phase modulation (SSPM), in a MoTe2 dispersion. The values of the third-order nonlinear optical coefficients effectively for one-layer MoTe2,.chi((3))(one-layer), are obtained through the SSPM method at excitation wavelengths 473, 532, 750, and 801 nm, respectively. The wind-chime model is used to explain the ring formation time. The wavelength dependence of chi((3))(one-layer) compares well with the photo-absorption spectra. Significantly, we find a correlation between. chi((3)) and the carrier mobility mu or effective mass m*, which again further supports the laser-induced ac electron coherence in 2D materials. (C) 2019 Optical Society of America.