Nanosecond Domain Wall Dynamics in Ferroelectric Pb ( Zr , Ti ) O 3 Thin Films

Department of Materials Science and Engineering, University of Wisconsin–Madison, Madison, Wisconsin, United States
Physical Review Letters (Impact Factor: 7.51). 06/2006; 96(18):187601. DOI: 10.1103/PhysRevLett.96.187601
Source: PubMed


Domain wall motion during polarization switching in ferroelectric thin films is fundamentally important and poses challenges for both experiments and modeling. We have visualized the switching of a Pb(Zr, Ti)O(3) capacitor using time-resolved x-ray microdiffraction. The structural signatures of switching include a reversal in the sign of the piezoelectric coefficient and a change in the intensity of x-ray reflections. The propagation of polarization domain walls is highly reproducible from cycle to cycle of the electric field. Domain wall velocities of 40 m s(-1) are consistent with the results of other methods, but are far less than saturation values expected at high electric fields.

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