This work is aimed at studying asymmetric ((BT) /(BZ)) superlattices, grown by pulsed laser deposition onto (001) MgO substrates. The thicknesses of BT (ferroelectric) and BZ (paraelectric) layers were varied so that х ranged from 0 to 1 at a modulation period of about 80 Å. The films were 400 nm thick. The out-of-plane lattice parameters of constituents were assessed using X-ray diffraction. The lattice dynamic peculiarities of superlattices were probed via Raman spectroscopy; special attention is paid to the analysis of E(1TO) and A1(2TO) ferroelectric soft modes. A comparative analysis of data acquired via both experimental techniques reveals the enhancement of stress between BT and BZ layers with a decrease in symmetry from the tetragonal to a monoclinic phase due to strains induced by the lattice parameter mismatch between the constituents.

中文翻译：

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X射线衍射和拉曼光谱分析不对称（BaTiO3）/（BaZrO3）超晶格的比较分析

这项工作旨在研究非对称性 （（BT）/（BZ））超晶格，通过脉冲激光沉积在（001）MgO衬底上生长。改变BT（铁电）和BZ（顺电）层的厚度，以使х在调制周期的范围从0到1约80Å。膜为400nm厚。使用X射线衍射评估成分的面外晶格参数。通过拉曼光谱研究了超晶格的晶格动力学特性。尤其要注意E（1TO）和A1（2TO）铁电软模的分析。通过两种实验技术获得的数据的比较分析显示，由于组分之间晶格参数不匹配而引起的应变，BT和BZ层之间的应力增强，从四方相到单斜相的对称性降低。