Related papers: Two-electron F' centers in alkali halides: A negat…
We are commenting on an earlier hypothesis of polaron states bound to F centers in alkali halides. These states increasing the effective size of the color centers, they play an active role in concentration-dependent phenomena, such as the…
The F' center in an alkali halide forms when an anion vacancy traps two electrons which is the prerequisite of a diatomic molecule. Indeed, the center may displace left or right along <110> in a (110) plane, due to its coupling to the…
We derive and discuss expressions for the temperature-dependent electrostatic polarizabilities of off-center ions holding good under various experimental conditions. At low temperatures and electric-field strengths, all of them reasonably…
The recombination of a free electron into a bound state of bare, heavy nucleus under simultaneous production of bound-electron--free-positron pair is studied within the framework of relativistic first--order perturbation theory. This…
Ensembles of negatively charged boron vacancy (V$_{\text{B}}^-$) centers in hexagonal boron nitride (hBN) have emerged as a two-dimensional spin qubit system interfaced with optics to advance nanoscale quantum sensing. However, a…
Extending earlier work on a vibronic theory of the FA centers in alkali halides, the reorientation is now considered of an off-center Li+ impurity, either isolated or near an F center. We derive analytically periodic potential energy…
The electronic states of Au-induced atomic nanowires on Ge(001) (Au/Ge(001) NWs) have been investigated by angle-resolved photoelectron spectroscopy with linearly polarized light. We have found three electron pockets around…
Subradiant excited states in finite chains of two-level quantum emitters coupled to a one-dimensional reservoir are a resource for superior photon storage and controlled photon manipulation. Typically, states storing multiple excitations…
Atomic negative ions are fragile quantum systems in which correlation among the valence electrons plays a very important role. For doubly excited states correlation becomes dominant. Photodetachment is the process where a negative ion…
Motivated by recent experiments [A. Lorke {\em et al.}, Phys. Rev. Lett.\ {\bf 84}, 2223 (2000)] an analysis of the ground state and far-infrared absorption of two electrons confined in a quantum ring is presented. The height of the…
We present a group theoretical and ab-initio analysis of lattice point defects in fluorographene, with a focus on neutral and negative $\text{V}_{\text{CF}}$ vacancies. By using a combination of density functional theory calculations and…
We report on multicolor excitation experiments with color centers in hexagonal boron nitride at cryogenic temperatures. We demonstrate controllable optical switching between bright and dark states of color centers emitting around 2eV.…
The scalar and tensor components of the electric quadrupole (E2) polarizabilities of the first two excited states of all the alkali-metal atoms are determined. To validate the calculations, we have evaluated the ground state E2…
We analyse the bound states of negatively charged ions which were predicted to exist because of the presence of a magnetic field by Avron et al. We confirm that the number of such states is infinite in the approximation of an infinitely…
The quantum entanglement for the two electrons in the excited states of the helium-like atom/ions is investigated using the two-electron wave functions constructed by the B-spline basis. As a measure of the spatial (electron-electron…
Embedded Si and Ge nanocrystals (NCs) in wide band-gap matrices are studied theoretically using an atomistic pseudopotential approach. From small clusters to large NCs containing on the order of several thousand atoms are considered.…
Optical and microwave double resonance techniques are used to obtain the excited state structure of single nitrogen-vacancy centers in diamond. The excited state is an orbital doublet and it is shown that it can be split and associated…
First-principles calculations reveal that the adsorption of representative first-row atoms with different electronegativity, such as lithium (Li), carbon (C) and fluorine (F), on zigzag single-walled boron nitride nanotubes (BNNTs) exhibits…
Previous studies have shown that dipole-bound excited states exist for certain small anions. However, valence excited states have been reported for some closed-shell anions, but those with singlet valence excited states have, thus far,…
Charge centers in ionic crystals provide a channel for elementary interaction between electromagnetic radiation and the lattice. We calculate the electronic ground state energies which are needed to create a charge center -- namely a $F$-…