Stabilization of monodomain polarization in ultrathin PbTiO3 films

作者:Fong DD*; Kolpak AM; Eastman JA; Streiffer SK; Fuoss PH; Stephenson GB; Thompson C; Kim DM; Choi KJ; Eom CB; Grinberg I; Rappe AM
来源:Physical Review Letters, 2006, 96(12): 127601.
DOI:10.1103/PhysRevLett.96.127601

摘要

Using in situ high-resolution synchrotron x-ray scattering, the Curie temperature T-C has been determined for ultrathin c-axis epitaxial PbTiO3 films on conducting substrates (SrRuO3 on SrTiO3), with surfaces exposed to a controlled vapor environment. The suppression of T-C was relatively small, even for the thinnest film (1.2 nm). We observe that 180 degrees stripe domains do not form, indicating that the depolarizing field is compensated by free charge at both interfaces. This is confirmed by ab initio calculations that find polar ground states in the presence of ionic adsorbates.

  • 出版日期2006-3-31