Domain inversion in ferroelectric MgO:LiNbO3 by applying electric fields

An antiparallel ferroelectric domain in LiNbO3 doped with 5 mol % MgO (MgO:LN) was inverted at room temperature by applying a step‐like electric field. The lowest electric field was about one fifth of that for undoped LN, but a high field compared to that for BaTiO3 was found to be necessary from the analysis of the switching current. The long switching time (about 102 s under an electric field of 4.45 kV/mm) enabled us to observe the domain growth process in MgO:LN. The needle‐shaped nuclei grew into larger domains by nucleation on the existing domain wall, and the wall of the coalesced domain moved forward slowly. The process was similar to the domain reversal model proposed for BaTiO3 under low electric fields.