相关论文: Dimensionality-induced change in topological order…
The emerging interest in two-dimensional electron gases (2DEGs), formed at interfaces between two insulating oxide perovskites poses crucial fundamental question in view of future electronic devices. In the framework of density-functional…
Interface physics in oxide heterostructures is pivotal in material's science. Domain walls (DWs) in ferroic systems are examples of naturally occurring interfaces, where order parameter of neighboring domains is modified and emerging…
We have analyzed the morphology of ferroelectric domains in very thin films of multiferroic BiFeO3. Unlike the more common stripe domains observed in thicker films BiFeO3 or in other ferroics, the domains tend not to be straight, but…
Magnetic spin topological textures recently found their electrical counterparts in polar topologies emerging from the condensation of inhomogeneous polar atomic distortions. Here, we further extend the concept to other non-polar atomic…
We perform real-time stereoscopic wide-area imaging of a ferroelectric phase-transition in KTN:Li. Spontaneous polarization is observed to form a thermally hysteretic 3D lattice of mutually interlinked closed-flux patterns that spans the…
Ferroelectrics are characterized by domain structures as are other ferroics. At the nanoscale though, ferroelectrics may exhibit non-trivial or exotic polarization configurations under proper electrostatic and elastic conditions. These…
The experimental observation that vanadate superlattices (LaVO$_3$)$_m$/SrVO$_3$ show ferromagnetism up to room temperature [U.\ L\"uders {\it et al.}, Phys.\ Rev.\ B {\bf 80}, 241102R (2009)] is investigated by means of density functional…
Using Landau-Ginzburg-Devonshire approach, we predict the intrinsic instability of the ferroelectric-ferroelastic domain walls in the multiferroic BiFeO3 emerging from the interplay between the gradient terms of the antiferrodistortive and…
Ferroelectric domain walls are quasi-2D systems that show great promise for the development of non-volatile memory, memristor technology and electronic components with ultra-small feature size. Electric fields, for example, can change the…
A set of broken symmetry two-dimensional ground states are predicted in (111)-oriented (LaNiO$_3$)$_N$/(LaAlO$_3$)$_M$ ($N$/$M$) superlattices, based on density functional theory (DFT) calculations including a Hubbard $U$ term. An…
We describe a new class of nanoscale structured metals wherein the effects of quantum confinement are combined with dispersive metallic electronic states to induce modifications to the fundamental low-energy microscopic properties of a…
We investigate the ferroelectric phase transition and domain formation in a periodic superlattice consisting of alternate ferroelectric (FE) and paraelectric (PE) layers of nanometric thickness. We find that the polarization domains formed…
Charged polar interfaces such as charged ferroelectric domain walls or heterostructured interfaces of ZnO/(Zn,Mg)O and LaAlO3/SrTiO3, across which the normal component of electric polarization changes suddenly, can host large…
Two-dimensional electron gas due to semiconductor interfaces can have high mobility and exhibits superconductivity, magnetism, and other exotic properties that are unexpected in constituent bulk materials. We study crystal structures,…
Deterministic polarization reversal in ferroelectric and multiferroic films is critical for their exploitation in nanoelectronic devices. While ferroelectricity has been studied for nearly a century, major discrepancies in the reported…
Antiferroelectrics are promising materials for high energy density capacitors and the search for environmentally-friendly and efficient systems is actively pursued. An elegant strategy to create and design new (anti)ferroic system relies on…
We report a first-principles study of (BaTiO${_3}$)$_m$/(BaO)$_n$ superlattices for a wide range of periodicities $m/n$. We show that such a system develops a polar zone-center instability for sufficiently large \textit{m}/\textit{n} ratio,…
We study the complex ferroelastic/ferroelectric domain structure in the prototypical ferroelectric PbTiO3 epitaxially strained on (110)o-oriented DyScO3 substrates, using a combination of atomic force microscopy, laboratory and synchrotron…
Artificially engineered superlattices were designed and fabricated to induce different growth mechanisms and structural characteristics. DC sputtering was used to grow ferromagnetic (La$_{0.8}$Ba$_{0.2}$MnO$_3$) / ferroelectric…
The ferroelectric domain pattern within lithographically defined PbTiO3/SrTiO3 ferroelectric/dielectric heteroepitaxial superlattice nanostructures is strongly influenced by the edges of the structures. Synchrotron x-ray nanobeam…