Shaanxi Key Laboratory of Condensed Matter Structures and Properties, Northwestern Polytechnical University, Xi'an, 710072, China.
Department of Physics, Xi'an Jiaotong University, Xi'an, 710072, China.
Sci Rep. 2017 Jul 24;7(1):6201. doi: 10.1038/s41598-017-06640-y.
In this paper, [(LaSrMnO)/(PaCaMnO)/(LaSbMnO)] superlattices films have been deposited on (001) Nb:SrTiO substrates by a laser molecular-beam epitaxy technology. Expected ferroelectricity arise at well-defined tricolor superlattice at low temperature, composed of transition metal manganite, which is absent in the single-phase compounds. Furthermore, the ferroelectric properties of the superlattices are enhanced by increasing the periodicity m, which may be attributed to the accumulation of the polarization induced by the frustration. As for the magnetic hysteresis loop characteristics of the multilayer structures, the saturation magnetization and magnetic coercivity of films present definitely a strong periodic dependence. It also indicates that the frustration may exist in the tricolor superlattice. Our results further verify the previous theoretical research of generating multiferroics experimentally paving a way for designing or developing the novel magnetoelectric devices based on manganite ferromagnets.
本文采用激光分子束外延技术在(001)Nb: SrTiO 衬底上沉积了[(LaSrMnO)/(PaCaMnO)/(LaSbMnO)]超晶格薄膜。在低温下，由过渡金属锰氧化物组成的三色超晶格具有明确的铁电性，而单相化合物中则没有铁电性。此外，通过增加周期性 m，超晶格的铁电性能得到增强，这可能归因于由受挫引起的极化的积累。对于多层结构的磁滞回线特性，薄膜的饱和磁化强度和磁矫顽力呈现出强烈的周期性依赖关系。这也表明在三色超晶格中可能存在受挫。我们的结果进一步验证了之前通过实验产生多铁性的理论研究，为设计或开发基于锰铁磁体的新型磁电器件铺平了道路。
