Noncontact scanning nonlinear dielectric microscopy imaging of TiO ₂ (110) surfaces

The authors simultaneously observed the typical topography and local electric dipole moment distribution of Ti atoms on a TiO₂ (110) 1×1 structure using noncontact scanning nonlinear dielectric microscopy (NC-SNDM). The upward polarization observed in polarization distribution images implies that the topography determined from the higher-order nonlinear dielectric constant signals is that of Ti⁴⁺. They also have examined the difference between the images formed by NC-SNDM and scanning tunneling microscopy. To acquire atomic resolution images using NC-SNDM, it was found that higher annealing temperatures were required.