论文标题
六角形tbmno中的应变驱动结构 - 弗洛电性关系$ _3 $电影
Strain-Driven Structure-Ferroelectricity Relationship in hexagonal TbMnO$_3$ Films
论文作者
论文摘要
最近，六角锰矿作为有前途的多效材料的薄膜和异质结构引起了人们的极大兴趣。我们报告了通过各种特征技术分析的高质量外延H-TMO/YSZ（111）膜的结构转换。通过温度依赖的拉曼光谱和光学椭圆法观察到从p63mc到p63mcm结构的相变。后者直接探测电子系统，表明其在可能是从氧到MN的电荷转移可能导致的结构相变过。 In situ transmission electron microscopy (TEM) of the lamella samples displayed an irreversible P63mc-P63mcm transformation and vanishing of ferroelectric domains already at 410 K. After the temperature cycling (300K-1300K-300K) the room temperature TEM of h-TMO films revealed an inhomogeneous microstructure, containing ferroelectric and paraelectric nanodomains with P63MC和P63MCM结构。我们指出了应力松弛的强烈影响，该释放是由温度和限制样品几何形状引起的结构，并在应变稳定的H-TMO薄膜中引起的铁电性。
Thin films and heterostructures of hexagonal manganites as promising multiferroic materials have attracted a considerable interest recently. We report structural transformations of high quality epitaxial h-TMO/YSZ(111) films, analyzed by means of various characterization techniques. A phase transition from P63mc to P63mcm structure at TC~800 K was observed by temperature dependent Raman spectroscopy and optical ellipsometry. The latter probing directly electronic system, indicates its modification at the structural phase transition likely due to charge transfer from oxygen to Mn. In situ transmission electron microscopy (TEM) of the lamella samples displayed an irreversible P63mc-P63mcm transformation and vanishing of ferroelectric domains already at 410 K. After the temperature cycling (300K-1300K-300K) the room temperature TEM of h-TMO films revealed an inhomogeneous microstructure, containing ferroelectric and paraelectric nanodomains with P63mc and P63mcm structure, respectively. We point out a strong influence of stress relaxation, induced by temperature and by constrained sample geometry onto the structure and ferroelectricity in strain-stabilized h-TMO thin films.
