Atomic force microscope studies on domain dynamics in phosphate substituted triglycine sulfate single crystals: Evidence for the domain boundary motion towards negative region and holes formation at the domain boundary

Domain dynamics in the (010) plane of phosphate substituted triglycine sulf ate (TGSP) crystals with time are investigated by atomic force microscopy. The domain boundary migration from positive to negative side and the simult aneous formation of holes are imaged for the first time. The holes are tran sformed from needle to round shape with time. The domain boundary movement occurs in order to reduce the total energy not only the surface but also bu lk energy. However, the formation of holes at the boundary may occur becaus e of insufficient supply of molecules from the surroundings and surface cha rge neutralization due to polarization reversal in the region.