Related papers: Dielectric dependent hybrid functionals for hetero…
The interaction of charges in dielectric materials is screened by the dielectric constant of the bulk dielectric. In dielectric theories, screening is assigned to the surface charge appearing from preferential orientations of dipoles along…
The electronic structure of Nickel dichalcogenides, NiS$_2$ and NiSe$_2$, in monolayer form, is studied employing first-principles methods. We assess the importance of band ordering, covalency and Coulomb interactions in the ground state of…
Starting from the random phase approximation for the weakly coupled multiband tightly-bounded electron systems, we calculate the dielectric matrix in terms of intraband and interband transitions. The advantages of this representation with…
Heterogeneous interfaces are central to many energy-related applications in the nanoscale. From the first-principles electronic structure perspective, one of the outstanding problems is accurately and efficiently calculating how the…
The near-field interaction of an atom with a dielectric surface is inversely proportional to the cube to the distance to the surface, and its coupling strength depends on a dielectric image coefficient. This coefficient, simply given in a…
Coulomb interactions play an essential role in atomically-thin materials. On one hand, they are strong and long-ranged in layered systems due to the lack of environmental screening. On the other hand, they can be efficiently tuned by means…
We study the atomic and electronic structures of ferroelectric perovskite oxides, BaTiO$_3$, LiNbO$_3$, and PbTiO$_3$ using ab initio extended Hubbard functionals in which the on-site and inter-site Hubbard interactions are determined…
We investigate band gaps, equilibrium structures, and phase stabilities of several bulk polymorphs of wide-gap oxide semiconductors ZnO, TiO2,ZrO2, and WO3. We are particularly concerned with assessing the performance of hybrid functionals…
The ability to perform first-principles calculations of electronic and vibrational properties of two-dimensional heterostructures in a field-effect setup is crucial for the understanding and design of next-generation devices. We present…
The electronic and optical properties of monolayer transition-metal dichalcogenides (TMDs) and van der Waals heterostructures are strongly subject to their dielectric environment. In each layer the field lines of the Coulomb interaction are…
Vertical stacking of two-dimensional (2D) crystals, such as graphene and hexagonal boron nitride, has recently lead to a new class of materials known as van der Waals heterostructures (vdWHs) with unique and highly tunable electronic…
Hybrid functionals' non-local exchange-correlation potential contains a derivative discontinuity that improves on standard semi-local density functional theory (DFT) band gaps. Moreover, by careful parameterization, hybrid functionals can…
We investigate how the renormalization of the band gap in a planar 2D material is affected by the consideration of two nondispersive semi-infinite dielectrics, with dielectric constants $\epsilon_1$ and $\epsilon_2$, separated by a planar…
Many-body functionals of the Green's function can provide fundamental advances in electronic-structure calculations, due to their ability to accurately predict both spectral and thermodynamic properties, such as angle-resolved photoemission…
The effective on-site Coulomb interaction (Hubbard $U$) between localized \textit{d} electrons in 3\textit{d}, 4\textit{d}, and 5\textit{d} transition metals is calculated employing a new parameter-free realization of the constrained…
In biological and synthetic materials, many important processes involve charges that are present in a medium with spatially varying dielectric permittivity. To accurately understand the role of electrostatic interactions in such systems, it…
The dynamical dielectric function of two dimensional graphene at arbitrary wave vector $q$ and frequency $\omega$, $\epsilon(q,\omega)$, is calculated in the self-consistent field approximation. The results are used to find the dispersion…
Unlike covalent two-dimensional (2D) materials like graphene, 2D metals have non-layered structures due to their non-directional, metallic bonding. While experiments on 2D metals are still scarce and challenging, density-functional theory…
We explore the roles of electronic band structure and Coulomb interactions in solid-state HHG by studying the optical response of linear atomic chains and carbon nanotubes to intense ultrashort pulses. Specifically, we simulate electron…
The use of effective local Coulomb interactions that are dynamical, that is, frequency-dependent, is an efficient tool to describe the effect of long-range Coulomb interactions and screening thereof in solids. The dynamical character of the…