Structure and energetics of ferroelectric domain walls in LiNbO$_{3}$ from atomic level simulations

Due to its unique ferroelectric and nonlinear optical properties, LiNbO$_{3}$ has a wide range of applications in optoelectronics and nonlinear optics. These unique properties of LiNbO$_{3}$ are, however, quite sensitive to point defects and ferroelectric domain walls. Therefore, detailed characterization of the ferroelectric domain walls and their interaction with the defects at atomistic scale is highly important The local structure and energetics of the ferroelectric domain walls in LiNbO$_{3}$ are examined using density functional theory (DFT) and atomistic-level simulation methods. The energetics and electric dipoles associated with the pertinent point defects and domain walls in LiNbO$_{3}$ are investigated in detail. In particular, the variation of polarization due to 180\r{ } ferroelectric domain walls, the coupling of defect-domain wall interactions and their effects on domain wall motion are discussed