International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
ACS Nano. 2010 Nov 23;4(11):6673-80. doi: 10.1021/nn102144s. Epub 2010 Nov 4.
Combining different materials into desired superlattice structures can produce new electronic states at the interface and the opportunity to create artificial materials with novel properties. Here we introduce a new, rather unexpected, and yet simple way to such a superlattice assembly of perovskite oxides: in the Dion-Jacobson phase, a model system of layered perovskites, high-quality bicolor perovskite superlattices (LaNb(2)O(7))(nL)(Ca(2)Nb(3)O(10))(nC) are successfully fabricated by a layer-by-layer assembly using two different perovskite nanosheets (LaNb(2)O(7) and Ca(2)Nb(3)O(10)) as a building block. The artificially fabricated (LaNb(2)O(7)/Ca(2)Nb(3)O(10)) superlattices are structurally unique, which is not feasible to create in the bulk form. By such an artificial structuring, we found that (LaNb(2)O(7)/Ca(2)Nb(3)O(10)) superlattices possess a new form of interface coupling, which gives rise to ferroelectricity.
将不同的材料组合成所需的超晶格结构可以在界面处产生新的电子态，并为创造具有新颖特性的人工材料提供机会。在这里，我们介绍了一种新的、相当出人意料但又很简单的方法来制备钙钛矿氧化物的超晶格组装体：在 Dion-Jacobson 相中，一种层状钙钛矿模型系统中，高质量双色钙钛矿超晶格（LaNb(2)O(7))(nL)(Ca(2)Nb(3)O(10))(nC) 通过使用两种不同的钙钛矿纳米片（LaNb(2)O(7)和 Ca(2)Nb(3)O(10))作为构建块的层层组装成功制备。人工制备的（LaNb(2)O(7)/Ca(2)Nb(3)O(10))超晶格具有独特的结构，这在体相中是不可能实现的。通过这种人工结构，我们发现（LaNb(2)O(7)/Ca(2)Nb(3)O(10))超晶格具有一种新的界面耦合形式，从而产生铁电性。
