Imaging of ferroelectric domain walls by force microscopy

We have imaged ferroelectric domain walls in the ferroelectric-ferroelastic material Gd2(MoO4)3 using force microscopy. By using a mode of imaging developed for the detection of static surface charge, the force gradient due to the polarization charge at the sample surface was imaged. The signal was seen to change sign at the domain wall, consistent with the reversal in sign of the polarization across a wall. By modeling the wall as a step function in the electric potential, the general features of the force microscope domain wall image could be explained.