Domain wall characterization in ferroelectrics by using localized nonlinearities.

In this paper, a method of domain wall characterization in ferroelectrics through Cherenkov second harmonic generation by localized nonlinearities is proposed. By this method, domain wall width is estimated to be less than 10nm. High spatial angular resolution of about 10 mrad in the experiment reveals the fine structures of the domain walls. Combined with scanning techniques, this method can reconstruct domain wall patterns with high resolution. This method has advantages of being nondestructive, noncontact, in situ as well as of high resolution.