相关论文: Defeating depolarizing fields with artificial flux…
The instability of ferroelectric ordering in ultra-thin films is one of the most important fundamental issues pertaining realization of a number of electronic devices with enhanced functionality, such as ferroelectric and multiferroic…
The balance between interfacial chemistry, electrostatics, and epitaxial strain plays a crucial role in stabilizing polarization in ferroelectric thin films. Here, we bring these contributions into competition in BiFeO$_3$ (BFO) thin films…
We study the ferroelectric stability and surface structural properties of an oxygen-terminated hexagonal YMnO$_3$ ultra-thin film using density functional theory. Under an open circuit boundary condition, the ferroelectric state with the…
Freestanding ferroelectric oxide membranes emerge as a promising platform for exploring the interplay between topological polar ordering and dipolar interactions that are continuously tunable by strain. Our investigations combining density…
Going down to the limit of ultrathin films holds promise for a new generation of devices such as ferroelectric tunnel junctions or resistive memories. However, these length scales also make the devices sensitive to parasitic effects related…
We present molecular dynamics simulations of a realistic model of an ultrathin film of BaTiO$_3$ sandwiched between short-circuited electrodes to determine and understand effects of film thickness, epitaxial strain and the nature of…
We simulate from first-principles the energetic, structural, and electronic properties of ferroelectric domains in ultrathin capacitors made of a few unit cells of BaTiO$_3$ between two metallic SrRuO$_3$ electrodes in short circuit. The…
A first-principles-derived approach is developed to study the effects of uncompensated depolarizing electric fields on the properties of Pb(Zr,Ti)O$_3$ ultrathin films for different mechanical boundary conditions. A rich variety of…
By performing first-principles calculations on four capacitor structures based on BaTiO3 and PbTiO3, we determine the intrinsic interfacial effects that are responsible for the destabilization of the polar state in thin-film ferroelectric…
Nanoscale electrostatic control of oxide interfaces enables physical phenomena and exotic functionalities beyond the realm of the bulk material. In technologically-relevant ferroelectric thin films, the interface-mediated polarization…
The control of the in-plane domain evolution in ferroelectric thin films is not only critical to understanding ferroelectric phenomena but also to enabling functional device fabrication. However, in-plane polarized ferroelectric thin films…
Magnetoelectric multiferroics, materials with intrinsically coupled electric polarization and magnetic order, promise ultralow-power switching, nonvolatile memory, and energy-efficient signal transduction. Yet practical deployment demands…
Ferroelectric domain walls are nanoscale objects that can be created, positioned, and erased on demand. They often embody functional properties that are distinct from the surrounding bulk material. Enhanced conductivity, for instance, is…
Integrating multiple properties in a single system is crucial for the continuous developments in electronic devices. However, some physical properties are mutually exclusive in nature. Here, we report the coexistence of two seemingly…
Based on first-principles and model calculations we investigate the effect of polar interfaces on the ferroelectric stability of thin-film ferroelectrics. As a representative model, we consider a TiO2-terminated BaTiO3 film with LaO…
Multiferroic BiFeO$_3$ (BFO) possesses a rich phase diagram that allows strain tuning of its properties in thin-film form. In particular, at large compressive strain, a supertetragonal (T) phase with giant polarization is stabilized over…
Surface and ferroelectric properties of PbTiO$_3$ thin films are investigated using an interatomic potential approach with parameters computed from first-principles calculations. We show that a model developed for the bulk describes…
The wealth of complex polar topologies recently found in nanoscale ferroelectrics result from a delicate balance between the materials intrinsic tendency to develop a homogeneous polarization and the electric and mechanic boundary…
Atomic-scale understanding of HfO2 ferroelectricity is important to help address many challenges in developing reliable and high-performance ferroelectric HfO2 (fe-HfO2) based devices. Though investigated from different angles, a factor…
The screening efficiency of a metal-ferroelectric interface plays a critical role in determining the polarization stability and hence the functional properties of ferroelectric thin films. Imperfect screening leads to strong depolarization…