Related papers: Solid solutions with coexisting antiferroelectric …
Metamaterials are artificial periodic structures which represent effective homogeneous medium for electromagnetic fields. Here I show that there exists an important class of such composite systems, metaferroelectrics. They are properly…
We show that, contrary to common belief, the depolarizing electric field generated by bound charges at thin-film surfaces can have a substantial impact on the domain structure of an improper ferroelectric with topological defects. In…
We propose a theoretical model of a ferroelectric metal where spontaneous electric polarization coexists with the conducting electrons. In our model we adopt a scenario when conducting electrons interact with two soft transverse optical…
Topological insulators are found in materials that have elements with strong spin orbit interaction. However, electron Coulomb repulsion also potentially generates the topological insulators as well as Chern insulators by the mechanism of…
Ferroelectric materials exhibit a switchable, spontaneous polarization at the unit cell level--an attractive property utilized in many emerging technologies including, among others, high-density memory storage, low-power transistors, and…
Materials undergoing antiferroelectric/ferroelectric (AFE/FE) transitions are studied for possible applications that exploit the large volume, charge and entropy differences between the two states, such as electrocaloric cooling, energy…
Molecular dynamics simulations predict a giant electrocaloric effect at the ferroelectric-antiferroelectric phase boundary in PZT (PbTiO$_3$-PbZrO$_3$). These large-scale simulations also give insights into the atomistic mechanisms of the…
We performed first principles calculations for epitaxially strained orthorhombic CaTiO$_3$. The computational results reveal the existence of a metastable ferroelectric phase at compressive strain with unexpected in-plane polarization.…
Superconducting systems may display different types of nonequilibrium states depending on the specific constraints imposed for measurement. We probe current-voltage relations of three-dimensional superconducting films by allowing finite…
The origin of the very large piezoelectric response observed in the vicinity of the morphotropic phase boundary (MPB) in perovskite lead zirconate titanate and related systems has been under intensive studies. Polarization rotation ideas…
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…
While nature provides a plethora of perovskite materials, only a few exhibits large ferroelectricity and possibly multiferroicity. The majority of perovskite materials have the non-polar CaTiO$_3$(CTO)structure, limiting the scope of their…
Fluorite structure ferroelectrics, especially hafnium oxide, are widely investigated for their application in non-volatile memories, sensors, actuators, RF devices and energy harvesters. Due to the metastable nature of the ferroelectric…
We theoretically explore mechanisms that can potentially give rise to the steady-state and transient negative capacitance in a uniaxial ferroelectric film stabilized by a dielectric layer. The analytical expressions for the steady-state…
In complex oxide heteroepitaxy, strain engineering is a powerful tool to obtain phases in thin films that may be otherwise unstable in bulk. A successful example of this approach is mixed phase bismuth ferrite (BiFeO3) epitaxial thin films.…
Fundamentally, lithium niobate is an extremely good electrical insulator. However, this can change dramatically when 180{\deg} domain walls are present, as they are often found to be strongly conducting. Absolute conductivities depend on…
Many ferroelectric solid solutions exhibit enhanced electro-mechanical properties at the morphotropic boundary separating two phases with different orientations of polarization. The mechanism of properties enhancement is associated with…
We investigate numerically the homogenized permittivities of composites made of low index dielectric inclusions in a ferroelectric matrix under a static electric field. A refined model is used to take into account the coupling between the…
Hybrid improper ferroelectrics (HIFs) have been intensely studied over the last few years to gain understanding of their temperature induced phase transitions and ferroelectric switching pathways. Here we report a switching from first- to…
The layered iron superconductors are discussed using electronic structure calculations. The four families of compounds discovered so far, including Fe(Se,Te) have closely related electronic structures. The Fermi surface consists of…