Abnormal piezoresponse behavior of Pb(Mg1/3Nb2/3)O3-30%PbTiO3 single crystal studied by high-vacuum scanning force microscope

The effect of vacuum level on the piezoresponse behavior of Pb(Mg_1/3Nb_2/3)O₃-30%PbTiO₃ (PMN-30%PT) single crystal has been investigated by scanning force microscopy (SFM) in the piezoresponse mode under high vacuum. Unusual piezoresponse behavior related to the screening charges compensation mechanism was observed on the surface of (1 1 1)-oriented crystal. The low piezoresponse signal detected by high-vacuum SFM is attributed to the instability of the polarization state that is caused by the insufficient compensation of the minor intrinsic screening charges for the polarization charges in PMN-30%PT single crystal under high vacuum condition. The high domain contrast of the sample at an ambient pressure is due to the dominant surface screening charges resulted from surface adsorption, which plays an important role in determining the stability of the domain behavior and in achieving the optimal properties for PMN-PT crystal with the composition near the morphotropic phase boundary. © 2003 Elsevier Science B.V. All rights reserved.