Multilayers and superlattices of ferroelectric barium strontium titanate

摘要

Epitaxial multilayers and superlattices of Ba_(0.8)Sr_(0.2)TiO_3 and Ba_(0.4)Sr_(0.6)TiO_3 were grown by pulsed laser deposition on MgO substrates using a La_(0.5)Sr_(0.5)CoO_3 bottom electrode. The epitaxial relations, crystal perfection, and strains were studied by x-ray diffraction at room temperature. Pseudomorphic growth of superlattices was demonstrated for the period as large as 62 unit cells. The obtained in-plane strain was consistent with that theoretically expected. Low-frequency functionality was found to depend on strain, period, and amount and quality of interfaces.