Domain wall roughness in stripe phase BiFeO3 thin films.
Using the model system of ferroelectric domain walls, we explore the effects of long-range dipolar interactions and periodic ordering on the behavior of pinned elastic interfaces. In piezoresponse force microscopy studies of the characteristic roughening of intrinsic 71° stripe domains in BiFeO3 thin films, we find unexpectedly high values of the roughness exponent ζ=0.74±0.10, significantly different from those obtained for artificially written domain walls in this and other ferroelectric materials. The large value of the exponent suggests that a random field-dominated pinning, combined with stronger disorder and strain effects due to the step-bunching morphology of the samples, could be the dominant source of pinning in the system.
DPMC-MaNEP, Université de Genève, 24 Quai Ernest Ansermet, 1211 Geneva, Switzerland.
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Ziegler
DPMC-MaNEP, Université de Genève, 24 Quai Ernest Ansermet, 1211 Geneva, Switzerland and LIPhy, Université Joseph Fourier Grenoble 1, UMR 5588 et CNRS, F-38402 Saint Martin d'Hères, France.
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Martens
DPMC-MaNEP, Université de Genève, 24 Quai Ernest Ansermet, 1211 Geneva, Switzerland.
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Giamarchi
DPMC-MaNEP, Université de Genève, 24 Quai Ernest Ansermet, 1211 Geneva, Switzerland.
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Paruch