Surface and Domain Structure of Pure PbTiO3, Mn-doped PbTiO3 and Pb(Zn1/2Nb1/2)0.91Ti0.09O3 Single Crystals by Atomic Force Microscopy

Nanometer scale surface morphologies in pure PbTiO3, Mn-doped PbTiO3 and Pb(Zn1/2Nb1/2)0.91Ti0.09O3 single crystals prepared by the flux method have been investigated by atomic force microscopy and discussed in connection with 90° and 180° domains. Regular gradiants with angles of 3.4° to 3.6° at the domain boundary were measured on the (001) surface in as-grown crystals with so-called typical 90° a-c domains. The angle of the gradiant is controlled by the crystal tetragonality ( c/a) in the crystal and is 3.4° to 3.6° in pure PbTiO3 and Mn-doped PbTiO3 with c/a=1.063, and 0.5° to 0.8° in Pb(Zn1/2Nb1/2)0.91Ti0.09O3 with c/a=1.004. In pure PbTiO3 and Mn-doped PbTiO3, the 180° c-c domains are constructed from the trapezoidal form with a step of 80 to 100 nm and confirmed by electric potential measurements using Kelvin force microscopy.