Piezoelectric response of nanoscale PbTiO3 in composite PbTiO3-CoFe2O4 epitaxial films

Piezoelectric properties of PbTiO3 in 1/3PbTiO(3)-2/3CoFe(2)O(4) transverse epitaxial nanostructures on differently oriented SrTiO3 were analyzed using conventional and switching-spectroscopy piezoelectric force microscopy. The results confirmed that the individual PbTiO3 nanocolumns in the CoFe2O4 matrix exhibit a detectable piezoelectric response regardless of substrate orientation. For the 100\ and 110\ orientations, a bias of +/- 10 V produced ferroelectric domain switching; however, no switching was observed for the 111\ films. Small values of piezoelectric constants d(zz)((100))approximate to 11 pm/V, d(zz)((110))approximate to 5 pm/V, and d(zz)((111))approximate to 3pm/V are attributed to the weak intrinsic response of the nano-PbTiO3 under strong mechanical and depolarizing-field constraints in the composite films. (c) 2008 American Institute of Physics.