The numerical approximation of the solution of the time-dependent Schrödinger equation arising in ultrafast laser dynamics is discussed. The linear Schrödinger equation is reduced to a computationally tractable, lower dimensional system of nonlinear partial differential equations by the multi-configuration time-dependent Hartree-Fock method. This method serves to approximate the original wave f...

An ab initio method is developed for variational grand-canonical molecular electronic structure of open systems based on the Gibbs-Peierls-Boguliobov inequality. We describe the theory and a practical method for performing the calculations within standard quantum chemistry codes using Gaussian basis sets. The computational effort scales similarly to the ground-state Hartree-Fock method. The qua...

We have developed a quantum Monte Carlo application for the computation of energy eigenvalues for atoms and ions in strong magnetic fields. We use guiding wave functions obtained by Hartree-Fock-Rothaan calculations. For these calculations, we use previously published code C. Schimeczek, D. Engel, G. Wunner, Comp. Phys. Comm. 183, 1502 – 1510 (2012)], as well as the recently developed 2DLHFR me...

This paper is devoted to the Hartree-Fock model with temperature in the euclidean space. For large classes of free energy functionals, minimizers are obtained as long as the total charge of the system does not exceed a threshold which depends on the temperature. The usual Hartree-Fock model is recovered in the zero temperature limit. An orbital stability result for the Cauchy problem is deduced...

We present results from Brueckner-Hartree-Fock calculations for b-stable neutron star matter with nucleonic and hyperonic degrees of freedom, employing the most recent parametrizations of the baryon-baryon interaction of the Nijmegen group. It is found that the only strange baryons emerging in b-stable matter up to total baryonic densities of 1.2 fm are S and L . The corresponding equations of ...

We calculate the magnetization of the two-dimensional electron gas in a short-period lateral superlattice, with the Coulomb interaction included in Hartree and Hartree-Fock approximations. We compare the results for a finite, mesoscopic system modulated by a periodic potential, with the results for the infinite periodic system. In addition to the expected strong exchange effects, the size of th...

Quantum many-body nuclear dynamics is treated at the mean-field level with the time-dependent Hartree-Fock (TDHF) theory. Low-lying and high-lying nuclear vibrations are studied using the linear response theory. The fusion mechanism is also described for light and heavy systems. The latter exhibit fusion hindrance due to quasi-fission. Typical characteristics of quasi-fission, such as contact t...

We review the Skyrme interaction as first used by Vautherin and Brink in the Hartree-Fock (HF) formalism to construct the energy density functional and more specifically, the two-body spin-orbit term. Problems with this term were already pointed out by Skyrme himself and have been discussed in the past years by other authors. We present examples where existing Skyrme parametrizations are unable...

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 neutrons are studied as a function of the density and the asymmetry of the system. The proton states are more strongly depleted when the asymmetry increases whe...

We study the thermodynamic phases of a gas of spin-1/2 atoms in the Hartree-Fock approximation. Our main result is that, for repulsive or weakly-attractive inter-component interaction strength, the superfluid and ferromagnetic phase transitions occur at the same temperature. For strongly-attractive inter-component interaction strength, however, the ferromagnetic phase transition occurs at a hig...