相关论文: Effects of dimensionality and anisotropy on the Ho…
We apply weak-coupling perturbation theory to the Holstein molecular crystal model in order to compute an electron-phonon correlation function characterizing the shape and size of the polaron lattice distortion in one, two, and three…
We study Holstein polarons in three-dimensional anisotropic materials. Using a variational exact diagonalization technique we provide highly accurate results for the polaron mass and polaron radius. With these data we discuss the…
We prove variationally that at weak coupling in one, two, and three dimensions there exist correlated electron-phonon states below the approximate ground states characteristically found by adiabatic polaron theory. Besides differing…
We present a detailed numerical study of the one-dimensional Holstein model with a view to understanding the self-trapping process of electrons or excitons in crystals with short-range particle-lattice interactions. Applying a very…
Based on a recently developed variational method, we explore the properties of the Holstein polaron on an infinite lattice in $D$ dimensions, where $ 1 \le D \le 4$. The computational method converges as a power law, so that highly accurate…
Employing a largely unbiased variational exact diagonalization technique, we analyze the consequences of longer-ranged electron hopping and electron-phonon interaction on polaron formation in one dimension. Having at our disposal the…
We adapt a variational procedure to calculate ground state properties of the Holstein model in the adiabatic limit. At strong coupling, this adaption leads to rapid convergence of results. The intermediate coupling regime is further handled…
The crossover from quasi free electron to small polaron in the Holstein model for a single electron is studied by means of both exact and self-consistent calculations in one dimension and on an infinite coordination lattice, in order to…
We present polaron effective masses and selected polaron band structures of the Holstein molecular crystal model in 1-D as computed by the Global-Local variational method over a wide range of parameters. These results are augmented and…
Anisotropic electron-phonon interaction is shown to lead to the anisotropic polaron effect. The resulting anisotropy of the polaron band is an exponential function of the electron-phonon coupling and might be as big as $10^3$. This also…
We analyze electron-phonon correlation functions measured in 1D polaron ground states of the Holstein Hamiltonian using the Global-Local variational method. The spatial collapse of electron-phonon correlations is found to occur in concert…
The polaron features of the one-dimensional Holstein Molecular Crystal Model are investigated by improving a variational method introduced recently and based on a linear superposition of Bloch states that describe large and small polaron…
The Holstein Molecular Crystal Model is investigated by a strong coupling perturbative method which, unlike the standard Lang-Firsov approach, accounts for retardation effects due to the spreading of the polaron size. The effective mass is…
The ground state of the Holstein molecular crystal model in one dimension is studied using the Global-Local variational method, analyzing in particular the total energy, kinetic energy, phonon energy, and interaction energy over a broad…
This study details the conditions under which strong-coupling perturbation theory can be applied to the molecular crystal model, a fundamental theoretical tool for analysis of the polaron properties. I show that lattice dimensionality and…
A perturbative study of the Holstein Molecular Crystal Model which accounts for lattice structure and dimensionality effects is presented. Antiadiabatic conditions peculiar of narrow band materials and an intermediate to strong…
A low order diagrammatic study of the dimension dependent Su-Schrieffer-Heeger model Hamiltonian in the weak electron-phonon coupling regime is presented. Exact computation of both the charge carrier effective mass and the electron spectral…
We study the effects of lattice type on polaron dynamics using a continuous-time quantum Monte-Carlo approach. Holstein and screened Froehlich polarons are simulated on a number of different Bravais lattices. The effective mass, isotope…
We derive an effective polaronic interaction Hamiltonian, {\it exact to second order in perturbation}, for the spinless one-dimensional Holstein model. The small parameter is given by the ratio of the hopping term ($t$) to the polaronic…
The single-polaron band structure of the Holstein model in one and two dimensions is studied using a new form of resummed strong-coupling perturbation theory. Well converged results are obtained for phonon frequencies of the order of the…