Related papers: Ab-initio investigation of Er3+ defects in tungste…
Ab-initio calculations for the electronic and optical properties of single-layer (SL) tungsten disulfide (WS$_2$) in the presence of substitutional Erbium defects (Er$_{\rm W}$) are presented, where the W atom is replaced by an Er atom.…
We investigate energetic and electronic properties of TiS2 , an archetypal van der Waals (vdW) material, from first principles, in the framework of the Density Functional Theory (DFT). In this system a recent experimental study showed a…
Erbium ions (Er3+) provide a telecom-band optical transition with strong magnetic-dipole character, making them attractive for quantum communication and spin-photon interfaces. Identifying host environments that combine low decoherence with…
The density functional theory (DFT) is used in a study of point defects on both UN (001) surface and sub-surface layers. We compare results for slabs of different thicknesses (both perfect and containing nitrogen or uranium vacancies) with…
The electronic and optical properties of single-layer (SL) tungsten disulfide (WS$_2$) in the presence of substitutional Holmium impurities (Ho$_{\rm W}$) are studied. Although Ho is much larger than W, density functional theory (DFT)…
Density functional theory (DFT) embedding provides a formally exact framework for interfacing correlated wave-function theory (WFT) methods with lower-level descriptions of electronic structure. Here, we report techniques to improve the…
Two-dimensional (2D) semiconducting transition metal dichalcogenides such as MoS$_2$ have attracted extensive research interests for potential applications in optoelectronics, spintronics, photovoltaics, and catalysis. To harness the…
The spin density wave (SDW) state of the uniform electron gas is investigated in the exact exchange approximation of noncollinear spin density functional theory (DFT). Unlike in Hartree-Fock theory, where the uniform paramagnetic state of…
This work reports an electronic and micro-structural study of an appealing system for optoelectronics: tungsten disulphide WS$_2$ on epitaxial graphene (EG) on SiC(0001). The WS$_2$ is grown via chemical vapor deposition (CVD) onto the EG.…
We propose a hybrid approach which employs the dynamical mean-field theory (DMFT) self-energy for the correlated, typically rather localized orbitals and a conventional density functional theory (DFT) exchange-correlation potential for the…
We present a first-principles study of defect formation and electronic structure of erbium (Er)-doped yttria (Y$_2$O$_3$). This is an emerging material for spin-photon interfaces in quantum information science due to the narrow linewidth…
The incorporation site of Er dopants inserted at high and low concentration (respectively 5 and 0.5 mol %) in nanoparticles of CaF 2 is studied by X-ray Absorption Spectroscopy (XAS) at the Er L III edge. The experimental data are compared…
In this work we use first-principles density-functional theory (DFT) calculations combined with the maximally localized Wannier function tight binding Hamiltonian (MLWF-TB) and Bethe-Salpeter equation (BSE) formalism to investigate…
We study the stability and electronic properties of intrinsic point defects, vacancy and self-interstitial, in mono- and bi-layer phosphorene. We calculate the formation energies, quasiparticle defect states and charge transition levels…
Understanding the luminescence of GaN doped with erbium (Er) requires a detailed knowledge of the interaction between the rare-earth dopant and the nitride host, including intrinsic defects and other impurities that may be present in the…
Control of impurity concentrations in semiconducting materials is essential to device technology. Because of their intrinsic confinement, the properties of two-dimensional semiconductors such as transition metal dichalcogenides (TMDs) are…
We apply Density Functional Theory (DFT) and the DFT+U technique to study the adsorption of transition metal porphine molecules on atomistically flat Au(111) surfaces. DFT calculations using the Perdew-Burke-Ernzerhof (PBE) exchange…
We present a formulation of spin-conserving and spin-flip, hybrid time-dependent density functional theory (TDDFT), including the calculation of analytical forces, which allows for efficient calculations of excited state properties of…
Many-body theories such as dynamical mean field theory (DMFT) have enabled the description of the electron exchange-correlation interactions that are missing in current density functional theory (DFT) calculations. However, there has been…
The addition of electron donors to the vacant A site of defect-perovskite structure tungsten trioxide causes a series of structural and chemical phase transitions; for instance, in the well-known case of the sodium tungsten bronzes…