Related papers: Self-consistent Green's function calculation of 16…
Thanks to improved methods for numerical analytic continuation with constraints, spectral functions with sharp features can now be extracted from imaginary-time correlation functions computed by quantum Monte Carlo (QMC) simulations. Here…
The spectral function of the closed-shell Neon atom is computed by expanding the electron self-energy through a set of Faddeev equations. This method describes the coupling of single-particle degrees of freedom with correlated two-electron,…
The second-order Matsubara Green's function method (GF2) is a robust temperature dependent quantum chemistry approach, extending beyond the random-phase approximation. However, till now the scope of GF2 applications was quite limited as…
Calculations of ground-state and excited-state properties of materials have been one of the major goals of condensed matter physics. Ground-state properties of solids have been extensively investigated for several decades within the…
We generate the perturbative expansion of the single-particle Green's function and related self-energy for a half-filled single-band Hubbard model on a square lattice. We invoke algorithmic Matsubara integration to evaluate single-particle…
An equation of motion phonon method, developed for even nuclei and recently extended to odd systems with a valence particle, is formulated in the hole-phonon coupling scheme and applied to A=15 and A=21 isobars with a valence hole. The…
We investigate the influence of a time dependent, homogeneous electric field on scattering properties of non-interacting electrons in an arbitrary static potential. We develop a method to calculate the (Keldysh) Green's function in two…
We introduce a computationally efficient approach to calculating the characteristics of excitons in quantum wells. In this approach we derive a system of self-consistent equations describing the motion of an electron-hole pair. The motion…
The electronic self-energy is studied for a two dimensional electron gas coupled to a spin-orbit Rashba field and interacting with dispersionless phonons. For the case of a momentum independent electron-phonon coupling (Holstein model) we…
The Green functions play a big role in the calculation of the local density of states of the carbon nanostructures. We investigate their nature for the variously oriented and disclinated graphene-like surface. Next, we investigate the case…
The quantum behavior of charge carriers in semiconductor structures is often described in terms of the effective mass Schr\"{o}dinger equation, neglecting the rapid fluctuations of the wave function on the scale of the atomic lattice. For…
Using the cluster expansions for n-point Green functions we derive a closed set of dynamical equations of motion for connected equal-time Green functions by neglecting all connected functions higher than $4^{th}$ order for the $\lambda…
We study ground-state properties of a two-site, two-electron Holstein model describing two molecules coupled indirectly via electron-phonon interaction by using both exact diagonalization and self-consistent diagrammatic many-body…
Multiphonon processes in a model quantum dot (QD) containing two electronic states and several optical phonon modes are considered taking into account both intra- and inter-level terms. The Hamiltonian is exactly diagonalized including a…
We use both a perturbative Green's function analysis and standard perturbative quantum mechanics to calculate the decrease in energy and the effective mass for an electron interacting with acoustic phonons. The interaction is between the…
Worm algorithm quantum Monte Carlo simulations of the hole Green function with subsequent spectral analysis were performed for J/t 0.1, 0.2, 0.4 on lattices with up to LxL=32x32 sites at temperatures as low as T=J/40, and present,…
The single-particle spectral functions in asymmetric nuclear matter are computed using the ladder approximation within the theory of finite temperature Green's functions. The internal energy and the momentum distributions of protons and…
A microscopic theory for electronic spectrum of the CuO2 plane within an effective p-d Hubbard model is proposed. Dyson equation for the single-electron Green function in terms of the Hubbard operators is derived which is solved…
Within the framework of many-particle perturbation theory, we develop an analytical approach that allows us to determine the small distance behavior of Green's functions and related quantities in electronic structure theory. As a case…
The retarded Green's function G(k,\omega) of a single small spin polaron in the three-band model for the CuO_2 plane is calculated in the self-consistent Born approximation. It is shown that such a spin polaron is a good quasiparticle…