Related papers: Dielectric mismatch and shallow donor impurities i…
Within the framework of staircase infinitely deep (SIW) potential well model the effect of dielectric constant mismatch between the size-quantized semiconducting wire, coating and surrounding environment on impurity binding energy is…
Within the effective mass approximation and variational method the effect of dielectric constant mismatch between the size-quantized semiconductor sphere, coating and surrounding environment on impurity binding energy in both the absence…
The effect of a constant electric field and donor impurity on the energies and oscillator strengths of electron intraband quantum transitions in double-well spherical quantum dot GaAs/Al$_{x}$Ga$_{1-x}$As/GaAs is researched. The problem is…
The problem of an impurity electron in a quantum ring (QR) in the presence of a radially directed strong external electric field is investigated in detail. Both an analytical and a numerical approach to the problem are developed. The…
The linewidths and the energy shifts of the resonant states of the impurity electron in GaAs-based quantum wells (QWs) with infinite barriers are calculated. The two-dimensional Schr\"{o}dinger equation for the charge impurity in the QW is…
We discuss the binding energy E_b of impurities in semiconductors within density functional theory (DFT) and the GW approximation, focusing on donors in nanowires as an example. We show that DFT succeeds in the calculation of E_b from the…
We present an atomistic description of the electronic and optical properties of $\text{In}_{0.25}\text{Ga}_{0.75}$N/GaN quantum wells. Our analysis accounts for fluctuations of well width, local alloy composition, strain and built-in field…
Understanding the electronic properties of dopants near an interface is a critical challenge for nano-scale devices. We have determined the effect of dielectric mismatch and quantum confinement on the ionization energy of individual…
We report on the achievement of a two-dimensional electron gas in completely undoped In[0.75]Al[0.25]As/In[0.75]Ga[0.25]As metamorphic quantum wells. Using these structures we were able to reduce the carrier density, with respect to…
The model of a spherical quantum dot with several donor impurities on its surface is suggested. The electron energy spectra are studied as a function of the quantum dot radius and the number of impurities. Several cases of the location of…
We present a general formulation of the ground state binding energy of a shallow hydrogenic impurity in spherical quantum dot with parabolic confinement, considering the effects of polarization and self energy. The variational approach…
We have studied the electronic and local magnetic structure of the hydrogen interstitial impurity at the tetrahedral site in diamond-structure Ge, using an empirical tight binding + dynamical mean field theory approach because within the…
We present a study of the effect of an electric field on the binding energy of a shallow hydrogenic impurity in GaAs/Ga_{1-x}Al_{x}As quantum well wires. The wire is considered to be of length L and radius R and the electric field F is…
The problem of electron binding states in field of two D0 centres in semiconductive quantum well (QW) in the presence of an external longitudinal magnetic field (along the QW growth axis) is studied within the framework of zero-range…
Using the perturbative scaling and the NRG, we study the characteristic energy scales in the Kondo impurity problem as a function of the exchange coupling constant $J$ and the conduction electron density. We discuss the relation between the…
We study theoretically the effect of an electric field on the electron states and far-infrared optical properties in narrow-gap lead salt quantum wells. The electron states are described by a two-band Hamiltonian. An application of a strong…
We consider the problem of electron energy states related to strongly localized potential of a single impurity in graphene. Our model simulates the effect of impurity atom substituting the atom of carbon, on the energy spectrum of electrons…
The effect of substitution atoms on the energy spectrum and the electrical conductivity of graphene was investigated in a Lifshitz one-electron tight-binding model. It is established that the ordering of impurity atoms results in a gap in…
We present a unified approach for calculating the properties of shallow donors inside or outside heterostructure quantum wells. The method allows us to obtain not only the binding energies of all localized states of any symmetry, but also…
A two-dimensional (2D) electron gas formed in a modulation-doped GaAs/AlGaAs single quantum well undergoes a first-order transition when the first excited subband is occupied with electrons, as the Fermi level is tuned into resonance with…