Interactions of Defects and Domain Walls in LiNbO3 – Insights from Simulations

Abstract

The defect formation energies of various possible defect complexes in stoichiometric LiNbO3 are calculated and the dominant defects are predicted based on their relative stabilities. The atomistic structure of one type of ferroelectric domain wall is discussed and the width of the domain wall is identified. Based on the analysis of polarization components normal to and transverse to the domain wall plane, it is found that domain walls exhibit Bloch and Neel like characteristics. Point defects are found to have lower formation energies at domain wall. Therefore, domain walls can be considered as trap sites of point defects.