Ferroelectric domain wall dynamics characterized with X-ray photon correlation spectroscopy.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29970423.
- Also identified by DOI 10.1073/pnas.1720991115 and PMC identifier 6055152.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Technologically important properties of ferroic materials are determined by their intricate response to external stimuli. This response is driven by distortions of the crystal structure and/or by domain wall motion. Experimental separation of these two mechanisms is a challenging problem which has not been solved so far. Here, we apply X-ray photon correlation spectroscopy (XPCS) to extract the contribution of domain wall dynamics to the overall response. Furthermore, we show how to distinguish the dynamics related to the passing of domain walls through the periodic (Peierls) potential of the crystal lattice and through the random potential caused by lattice defects (pinning centers). The approach involves the statistical analysis of correlations between X-ray speckle patterns produced by the interference of coherent synchrotron X-rays scattered from different nanosize volumes of the crystal and identification of Poisson-type contribution to the statistics. We find such a contribution in the thermally driven response of the monoclinic phase of a ferroelectric PbZr<sub>0.55</sub>Ti<sub>0.45</sub>O<sub>3</sub> crystal and calculate the number of domain wall jumps in the studied microvolume.