| AVS 63rd International Symposium & Exhibition | |
| Surface Science | Wednesday Sessions |
| Session SS+2D-WeM |
| Session: | Synthesis, Characterization, and Surface Science of Novel Materials and Interfaces |
| Presenter: | Erie Morales, The University of Pennsylvania |
| Authors: | E. Morales, The University of Pennsylvania C. Perez, The University of Pennsylvania M. Brukman, The University of Pennsylvania D. Bonnell, The University of Pennsylvania |
| Correspondent: | Click to Email |
The local measurement of structure and properties enabled by scanning tunneling microscopy and atomic force microscopy in conjunction with systematic control of in situ environments has yielded insight into the fundamental behavior of ferroelectric compounds. Many atomic structures on BaTiO3 surfaces have been determined, the thermodynamic stability of structures on (001) surfaces has been described, and the polarization dependence of several classes of surfaces reactions has been demonstrated. In addition the polarization behavior at the nanoscale has received much attention.
Here we report unusual impact of local poling on the electronic structure of ferroelectric surfaces. Scanning Tunneling Microscopy in situ poling was performed on BaTiO3 (001) in ultra high vacuum (UHV). The voltage pulse produces apparent anti-parallel ferroelectric domains. Domain size can be controlled by changing conductivity of the crystal and/or by changing the bias set point; the smallest domain we pole is 24 nm. We use a 4-D analysis of geometric and electronic structure data to characterize the variations in electronic structure. Patterns of variations in the surface band gap are consistent with existing theoretical calculations of anti parallel domain orientations.