Optical characterizations of two-dimensional materials using nonlinear optical microscopies of CARS, TPEF, and SHG

In this paper, we employ the nonlinear optical microscopies of coherent anti-Stokes Raman scattering spectroscopy, two-photon excitation fluorescence, and second harmonic generation to characterize the properties of two-dimensional (2D) materials. With these nonlinear optical microscopy methods, we can not only clearly observe the surface topography of 2D materials but also reveal the quality of 2D materials. These nonlinear optical microscopies offer great potential for characterization of the properties of 2D materials.