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تسجيل مستخدم جديدFerroelectric nanodomains in epitaxial PbTiO3 films grown on SmScO3 and TbScO3 substrates
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Domain structures of 320 nm thin epitaxial films of ferroelectric PbTiO3 grown by MOCVD technique in identical conditions on SmScO3 and TbScO3 perovskite sub- strates have been investigated by Raman spectroscopy and piezoresponse force microscopy techniques. Phonon frequency shifts and typical domain structure motifs are discussed. The results reveal strikingly different domain structure architecture: domain structures of the PbTiO3 film grown on SmScO3 have dominantly a-domain orientation while strongly preferential c-domain orientation was found in the PbTiO3 film grown on the TbScO3 substrate. Differences between the two cases are traced back to the film-substrate lattice mismatch at the deposition temperature.
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