Polarization Switching without Domain Formation at the Intrinsic Coercive Field in Ultrathin Ferroelectric PbTiO 3

Argonne National Laboratory, Argonne, Illinois 60439, USA.
Physical Review Letters (Impact Factor: 7.51). 10/2010; 105(16):167601. DOI: 10.1103/PhysRevLett.105.167601
Source: PubMed


Polarization switching in ferroelectrics has been thought to occur only through the nucleation and growth of new domains. Here we use in situ synchrotron x-ray scattering to monitor switching controlled by applied chemical potential. In sufficiently thin PbTiO₃ films, nucleation is suppressed and switching occurs by a continuous mechanism, i.e., by uniform decrease and inversion of the polarization without domain formation. The observed lattice parameter shows that the electric field in the film during switching reaches the theoretical intrinsic coercive field.

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    • "What we are interested in is whether it has a continuous polarization switching without domain formation (continuous mechanism). Continuous mechanism has been studied in PbTiO 3 [17] and this mechanism will not cause fatigue because according to domain wall pinning mechanism, electrostatic coupling between a non-neutral domain wall and mobile carriers forms a pined electro-neutral structure [18]. "
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