Related papers: Approximation of excitonic absorption in disordere…
A variant of coupled-cluster theory is described here, wherein the degrees of freedom are fluctuations of fragments between internally correlated states. The effects of intra-fragment correlation on the inter-fragment interaction are…
Exciton effects on soliton and bipolaron lattice states are investigated using an electron-lattice Peierls model with long-range Coulomb interactions. The Hartree-Fock (HF) approximation and the single-excitation configuration-interaction…
The effects of doping on the spectral properties of low doped systems are investigated by means of Coherent Potential Approximation to describe the distributed disorder induced by the impurities and Phonon-Phonon Non-Crossing Approximation…
It is shown that the errors of present-day exchange-correlation (xc) functionals are rather short ranged. For extended systems the correction can therefore be evaluated by analyzing properly chosen clusters and employing highest-quality…
Based on distributions of local Green's functions we present a stochastic approach to disordered systems. Specifically we address Anderson localisation and cluster effects in binary alloys. Taking Anderson localisation of Holstein polarons…
A coherent description of the anomalous Hall effect (AHE) is presented that is applicable to pure as well as disordered alloy systems by treating all sources of the AHE on equal footing. This is achieved by an implementation of the…
Exciton polaritons, arising from the interaction of electronic transitions with confined electromagnetic fields, have emerged as a powerful tool to manipulate the properties of organic materials. However, standard experimental and…
The band structure of $\beta$-LiGaO$_2$ is calculated using the quasiparticle self-consistent QS$G\hat W$ method where the screened Coulomb interaction $\hat W$ is evaluated including electron-hole interaction ladder diagrams and $G$ is the…
The Anderson model with the Coulomb interaction between the local and conduction electrons is studied in the semiconducting phase. Based on a perturbation theory from the atomic limit, leading contributions for the c-f Coulomb interaction…
Charge-density-wave (CDW) order in correlated metals originates in a peaked electronic susceptibility at a finite wavevector $\mathbf Q_0$, set either by Fermi-surface features (nesting or saddle-point singularities) or by momentum-resolved…
We provide a self-contained review of master equation approaches to modelling phonon effects in optically driven self-assembled quantum dots. Coupling of the (quasi) two-level excitonic system to phonons leads to dissipation and dephasing,…
An externally corrected coupled cluster (CC) method, where an adaptive configuration interaction (ACI) wave function provides the external cluster amplitudes, named ACI-CC, is presented. By exploiting the connection between configuration…
Since the early 1960s, alloys are commonly grouped into two classes, featuring bound states in the bandgap (I) or additional, non-discrete band states (II). Microscopic material parameters for class I alloys can directly be extracted from…
We introduce a generalization of Wegner's $n$-orbital model for the description of randomly disordered systems by replacing his ensemble of Gaussian random matrices by an ensemble of randomly rotated matrices. We calculate the one- and…
In the framework of the many-electron s-d exchange model and Hubbard model, self-consistent equations are derived for the one-particle retarded Green's function in the many-electron Hubbard X-operator representation. We analyze the general…
The modeling of solute chemistry at low-symmetry defects in materials is historically challenging, due to the computation cost required to evaluate thermodynamic properties from first principles. Here, we offer a hybrid multiscale approach…
We present a longitudinal electrical conductivity calculation method for disordered alloys applicable from a wide range of density functional theory (DFT) codes based on the first-principles Wannier-based coherent potential approximation…
We present a fully atomistic approach to exciton-phonon coupling in semiconductor quantum dots that bridges microscopic electronic-structure calculations with non-Markovian open-quantum-system dynamics. On the example of an InAsP quantum…
A new perturbational approach to spectral and thermal properties of strongly correlated electron systems is presented: The Anderson model is reexamined for $U\to\infty$\,, and it is shown that an expansion of Green's functions with respect…
We show that the electron-phonon coupling (EPC) in many materials can be significantly underestimated by the standard density functional theory (DFT) in the local density approximation (LDA) due to large non-local correlation effects. We…