Related papers: Ferroelectric instability of two-dimensional cryst…
Flexoelectricity is a form of electromechanical coupling that has recently emerged because, unlike piezoelectricity, it is theoretically possible in any dielectric material. Two-dimensional (2D) materials have also garnered significant…
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…
Recent observations of unusual ferroelectricity in thin films of HfO_2 and related materials have attracted broad interest to the materials and led to the emergence of a number of competing models for observed behaviors. Here we develop the…
The recent observation of a ferroelectric-like structural transition in metallic LiOsO$_3$ has generated a flurry of interest in the properties of polar metals. Such materials are thought to be rare because free electrons screen out the…
Collinear dipole orders such as ferroelectricity and antiferroelectricity have developed rapidly in last decades. While, the noncollinear dipole orders are rarely touched in solids. Noncollinear dipole orders can provide a route to realize…
We analyze a system of polar molecules in a one-dimensional optical lattice. By controlling the internal structure of the polar molecules with static electric and microwave fields, we demonstrate the appearance of a quantum phase transition…
Two-dimensional (2D) ferroelectrics and multiferroics have attracted considerable scientific and technological interest in recent years due to the increasing demands for miniaturization and low energy consumption of electronic devices. At…
Using density functional theory we investigate the lattice instability and electronic structure of recently discovered ferroelectric metal LiOsO$_3$. We show that the ferroelectric-like lattice instability is related to the Li-O distortion…
Twisted heterostructures of two-dimensional crystals can create a moir\'{e} landscape, which can change the properties of it's parent crystals. However, the reproducibility of manual stacking is far from perfect. Here, the alternated…
It was recently observed that materials showing most striking multiferroic phenomena are frustrated spin-density-wave magnets. We present a simple phenomenological theory, which describes the orientation of the induced electric polarization…
Ferroelectric crystals must adopt one of the 10 polar point groups according to the Neumann's principle. In this paper we propose that this conclusion is based on perfect bulk crystals without taking the boundaries into account, and we show…
Two dimensional (2D) atomic crystals of graphene, and transition metal dichalcogenides have emerged as a class of materials that show strong light-matter interaction. This interaction can be further controlled by embedding such materials…
Two-dimensional polar liquid crystals have been discovered recently in monolayers of anisotropic molecules. Here, we provide a systematic theoretical description of liquid-crystalline phases for polar particles in two spatial dimensions.…
The electrodynamics of two-dimensional (2D) dielectric and conducting layers cannot be described by such three-dimensional macroscopic quantities as the dielectric constant $\epsilon$ or the refractive index $n$. By means of the proper…
Organic ferroelectric materials are in demand in the growing field of environmentally friendly, lightweight electronics. Donor-Acceptor charge transfer crystals have been recently proposed as a new class of organic ferroelectrics, which may…
Ferroelectricity usually fades away when materials are thinned down below a critical value. Employing the first-principles density functional theory and modern theory of polarization, we show that the unique ionic-potential anharmonicity…
Polar metals with ferroelectric-like displacements in metals have been achieved recently, half century later than Anderson and Blount's prediction. However, the genuine ferroelectricity with electrical dipolar switching has not yet been…
It is of great interest to design and make materials in which ferroelectric polarisation is coupled to other order parameters such as lattice, magnetic and electronic instabilities. Such materials will be invaluable in next-generation data…
Electrical control of magnetization or magnetic control of polarization offers an extra degree of freedom in materials possessing both electric and magnetic dipole moments viz., magnetoelectric multiferroics. Microstructure with…
Advances in first-principles computational approaches have, over the past fifteen years, made possible the investigation of physical properties of ferroelectric systems. In particular, such approaches have led to a microscopic understanding…