V001 / JSI / T589

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Researchers from Jožef Stefan Institute (Electronic Ceramics Department), National Institute of Chemistry, Ecole Polytechnique Fédérale de Lausanne, Materials Center Leoben and Tokyo Institute of Technology published a study in Nature Communications entitled Atomic scale symmetry and polar nanoclusters in the paraelectric phase of ferroelectric materials.The study provides structural details of polar nanoscale clusters whose hypothetical presence in the paraelectric phase of perovskite ferroelectrics has been discussed for decades. Using an atomic-resolution study by scanning transmission electron microscopy complemented by Raman spectroscopy, they directly reveal, visualize, and quantitatively describe static 2-4 nm large polar nanoclusters in the nominally nonpolar cubic phases of barium titanate based ceramics. The probable reason for the stabilization is the presence of local strains, which originate from the size difference between additives, vacancies and host ions. These results have implications for understanding the atomic-scale structure of disordered materials and may help clarify ambiguities about the dynamic-versus- static nature of nano-sized clusters.