Fig. 1. Two-dimensional materials and nonlinear optics

Fig. 2. Layer number dependence of SHG in 2D materials

Fig. 3. Layer number dependence of THG in 2D materials

Fig. 4. Imaging crystal axis of 2D materials by SHG

Fig. 5. Investigation of grain boundaries in 2D materials based on SHG imaging

Fig. 6. Nonlinear optical imaging in 2D homostructures

Fig. 7. Nonlinear optical imaging in 2D heterostructures

Fig. 8. Nonlinear optical microscopic images of 2D materials under modulation by external fields

Fig. 9. Impact of SPPs on nonlinear optical responses of 2D materials

Fig. 10. Nonlinear optical imaging of 2D materials beyond diffraction limit