Domain inversion in LiNbO3 and LiTaO3 induced by proton exchange

This review paper reports the studies on ferroelectric domain inversion and inverse mechanism in ferroelectric and dielectric LiNbO3 and LiTaO3 single crystals by proton exchange followed by heat treatment. Secondary ion mass spectroscopy and numerical simulation of proton profile, differential scanning calorimetry, pyroelectric experiment and transmission electron microscopy were used to characterize the domain inversion. The inverse mechanism was discussed by means of an internal electric field model, which is based on the concentration gradient of proton and lithium deficiency.