Engineered Interfaces of Artificial Perovskite Oxide Superlattices via Nanosheet Deposition Process

Abstract

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.

Recent development in 2D materials beyond graphene

“…Nanostructured films obtained from both, electrostatic sequential deposition and LB deposition process, demonstrate good interlayer registry ( Figure. 30b) [561][562][563]. This welldefined registry develops novel properties in the nanostructured film [561].…”

Fabrication and convergent X-ray nanobeam diffraction characterization of submicron-thickness SrTiO3 crystalline sheets

“…[4][5][6] Alternative approaches based on chemical exfoliation of large-unit-cell oxide compounds can create ultrathin substrates but have a severely limited range of compositions and crystallographic orientations. 7 In this Letter we report the creation and characterization of submicron-thickness SrTiO 3 (STO) sheets. The results demonstrate that focused ion beam (FIB) lithography techniques can be used to create a thin STO sheet with sufficiently low defect densities to allow subsequent use as substrates for thin film growth.…”

“…Exfoliated sheets with thicknesses at the unit-cell scale can be fabricated using a colloidal suspension of perovskite sheets from a Dion-Jacobson phase. 7 Exfoliation, however, yields a narrow range of thicknesses, on the order of 1-2 nm, has fixed (001) orientation set by the layering of the parent phase, and relatively small micron-scale crystals. A second method, epitaxial growth and lift-off, involves etching a sacrificial layer and transfer to a new substrate.…”

Chemical Nanomanipulation of Two-Dimensional Nanosheets and Its Applications

“…4(b)]. [42][43][44][45] LB film deposition, the formation of a floating monolayer on water surface in a Langmuir trough followed by an appropriate level of compression, is preferable for achieving dense packing or neat tiling. Through verticaldipping/lifting, the monolayer is deposited onto a flat substrate in LbL fashion.…”