相关论文: Anion order and spontaneous polarization in LaTiO\…
Perovskite oxynitrides have recently attracted attention for their ability to photocatalytically split water. Compared to oxides the arrangement of anions in the material represents a further structural degree of freedom. The bulk…
Anionic ordering is a promising route to engineer physical properties in functional heteroanionic materials. A central challenge in the study of anion-ordered compounds lies in developing robust synthetic strategies to control anion…
We investigate the variation of the spontaneous ferroelectric polarization with epitaxial strain for BaTiO$_3$, PbTiO$_3$, LiNbO$_3$, and BiFeO$_3$ using first principles calculations. We find that while the strain dependence of the…
We investigate energetically favorable structures of ABO$_2$N oxynitrides as functions of pressure and strain via swarm-intelligence-based structure prediction methods, DFT lattice dynamics and first-principles molecular dynamics. We…
Transition-metal heterostructures offer the fascinating possibility of controlling orbital degrees of freedom via strain. Here, we investigate theoretically the degree of orbital polarization that can be induced by epitaxial strain in…
A combined experimental and computational investigation of coupling between polarization and epitaxial strain in highly polar ferroelectric PbZr_0.2Ti_0.8O_3 (PZT) thin films is reported. A comparison of the properties of relaxed…
Perovskite oxynitrides are a promising class of material for photocatalytic water-splitting due to their small band gaps and suitably aligned band edges. Recently, epitaxially strained oxynitrides started to attract interest due to the…
We address the fundamental issue of growth of perovskite ultra-thin films under the condition of a strong polar mismatch at the heterointerface exemplified by the growth of a correlated metal LaNiO$_3$ on the band insulator SrTiO$_3$ along…
In pursuit of rational control of orbital polarization, we present a combined experimental and theoretical study of single unit cell superlattices of the correlated metal LaNiO$_3$ and the band insulator LaAlO$_3$. Polarized x-ray…
Strain engineering of perovskite oxide thin films has proven to be an extremely powerful method for enhancing and inducing ferroelectric behavior. In ferroelectric thin films and superlattices, the polarization is intricately linked to…
Thin films of PbTiO3, a classical ferroelectric, have been grown under tensile strain on single-crystal substrates of DyScO3. The films, of only 5nm thickness, grow fully coherent with the substrate and show no crystallographic twin…
The size of the band gap and the energy position of the band edges make several oxynitride semiconductors promising candidates for efficient hydrogen and oxygen production under solar light illumination. The intense research efforts…
Strontium titanate is an incipient ferroelectric in which superconductivity emerges at exceptionally low doping levels. Remarkably, stabilizing the polar phase through strain or chemical substitution has been shown to significantly enhance…
The surface charge associated with the spontaneous polarization in ferroelectrics is well known to cause a depolarizing field that can be particularly detrimental in the thin-film geometry desirable for microelectronic devices. Incomplete…
Pure NaNbO$_{3}$ is an antiferroelectric material at room temperature that irreversibly transforms to a ferroelectric polar state when subjected to an external electrical field or lattice strain. Experimentally, it has been observed that…
A fundamental understanding of the interplay between lattice structure, polarization and electrons is pivotal to the optical control of ferroelectrics. The interaction between light and matter enables the remote and wireless control of the…
For decades, numerous attempts have been made to produce polar oxynitride perovskites, where some of the oxygen are replaced by nitrogen, but a polar ordered oxynitride has never been demonstrated. Caracas and Cohen studied possible ordered…
In this work, we use density functional theory calculations to demonstrate how spontaneous electric polarizations can be induced \textit{via} a hybrid improper ferroelectric mechanism in iodide perovskites, a family well-known to display…
We have used polarized Raman scattering to probe lattice vibrations and charge ordering in 12 nm thick, epitaxially strained PrNiO$_3$ films, and in superlattices of PrNiO$_3$ with the band-insulator PrAlO$_3$. A carefully adjusted confocal…
Layered perovskite-based compounds offer a range of unconventional properties enabled by their naturally anisotropic structure. While most renowned for the superconductivity observed in the Ruddlesden-Popper phases, many of these layered…