相关论文: Berry-phase theory of polar discontinuities at oxi…
First-principles modeling of ferroelectric capacitors presents several technical challenges, due to the coexistence of metallic electrodes, long-range electrostatic forces and short-range interface chemistry. Here we show how these aspects…
We consider the flow of polarization current J(t)=dP/dt produced by a homogeneous electric field E(t) or by rapidly varying some other parameter in the Hamiltonian of a solid. For an initially insulating system and a collisionless time…
LaAlO$_{3}$/SrTiO$_{3}$ heterostructure with polar and non-polar constituents has been shown to exhibit interface metallic conductivity due to fractional charge transfer to the interface. The interface reconstruction by electron…
A perturbation theory of the static response of insulating crystals to homogeneous electric fields, that combines the modern theory of polarization (MTP) with the variation-perturbation framework is developed, at unrestricted order of…
Discontinuity of dielectric constants at the interface is a common feature of all nanostructures and semiconductor heterostructures. Near such interfaces, a charged particle creates a singular self-interaction potential which may be…
We provide a unified semiclassical theory for thermoelectric responses of any observable represented by an operator $\hat{\boldsymbol{\theta}}$ that is well-defined in periodic crystals. The Einstein and Mott relations are established…
The recent discovery of 2D superconductivity at the interface of BaPbO$_3$ (BPO) and BaBiO$_3$ (BBO) has motivated us to study in depth the electronic and structural properties and the relation between them in this particular…
In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion-symmetry across the heterointerfaces. A notable example is the interface between polar and non-polar…
Polar discontinuities and structural changes at oxide interfaces can give rise to a large variety of electronic and ionic phenomena. Related effects have been intensively studied in epitaxial systems, including ferroelectric domain walls…
It is nowadays a quite diffuse idea that variations of polarisation in condensed matter theory are related to a "Berry phase". The derivation of the latter geometric phase is correct $\it{only if}$ the restrictive periodic gauge\cite{KS-V}…
Ferroelectricity, a hallmark of spontaneous inversion-symmetry breaking, has been a central concept in condensed matter physics and functional materials research, yet recent discoveries are revealing that switchable polarization can emerge…
We present a systematic approach to modeling the electrical and structural properties of charge-mismatched superlattices from first principles. Our strategy is based on bulk calculations of the parent compounds, which we perform as a…
Recently, it has been shown how topological phases of matter with crystalline symmetry and $U(1)$ charge conservation can be partially characterized by a set of many-body invariants, the discrete shift $\mathscr{S}_{\text{o}}$ and electric…
We formulate a framework for the depolarization of linearly polarized backscattered light based on the concept of geometric phase, {\it i.e} Berry's phase. The predictions of this theory are applied to the patterns formed by backscattered…
Core concepts in singular optics, especially the polarization singularity, have rapidly penetrated the surging fields of topological and nonhermitian photonics. For open photonic structures with degeneracies in particular, the polarization…
The dipole moment of any finite and neutral system, having a square-integrable wavefunction, is a well defined quantity. The same quantity is ill-defined for an extended system, whose wavefunction invariably obeys periodic (Born-von Karman)…
The response of an infinite, periodic, insulating, solid to an infinitesimally small electric field is investigated in the framework of Density Functional Theory. We find that the applied perturbing potential is not a unique functional of…
A modified model of metal-semiconductor contacts is applied to analyze the capacitance-voltage and current-voltage characteristics of metal-ferroelectric-metal structures. The ferroelectric polarization is considered as a sheet of surface…
Motivated by recent experiments with ultra-cold matter, we derive a new bound on the propagation of information in $D$-dimensional lattice models exhibiting $1/r^{\alpha}$ interactions with $\alpha>D$. The bound contains two terms: One…
Topological insulators are substances which are bulk insulators but which carry current via special "topologically protected" edge states. The understanding of long range topological order in these systems is built around the idea of a…