PACS 03.70+k, 32.70.Cs, 42.50.Ct We investigate (non-relativistic) atomic systems interacting with quantum electromagnetic field (QEF). The resulting model describes spontaneous emission of light from a two-level atom surrounded by various initial states of the QEF. We assume that the quantum field interacts with the atom via the standard, minimalcoupling Hamiltonian, with the A term neglected....

Crystal binding energy of a core electron at the 3d5/2 level of a Pd atom has been estimated to be −4.0 ± 0.02 eV by decoding the X-ray photoelectron spectra obtained from both the Pd surfaces and the Pd nanoparticles. Findings indicate that the increase in the binding energy originates from the effect of coordination number (CN) imperfection of atoms at a flat surface or at the curved surface ...

In this review we discuss quantum phase transitions and the mapping between symmetry breaking of electronic structure con® gurations at the large-dimension limit and mean-® eld theory of phase transitions. We show that the ® nite size scaling method can be used for the calculations of the critical parameters of the few-body Schr È odinger equation. In this approach, the ® nite size corresponds ...

A simple procedure to incorporate one-loop quantum electrodynamic (QED) corrections into the generalized (Gatchina) nonlocal shape-consistent relativistic pseudopotential model is described. The pseudopotentials for Lu, Tl, and Ra replacing only inner core shells (with principal numbers $n\le 3$ two former elements 4$ latter one) are derived from solutions of reference atomic SCF problems with ...

2014 Static multipole polarizabilities of S atoms or ions have been calculated by two equivalent variational methods. Our results are in harmony with an earlier work which used the uncoupled Hartree-Fock approximation. LE JOURNAL DE PHYSIQUE TOME 40, FÉVRIER 1979, Classification Physics Abstracts 31.10 Recently we reported [1] a variational treatment for static multipole polarizabilities of ato...

Ultracold atoms in optical lattices are promising systems to realize and study novel quantum mechanical phases of matter with the control and precision offered by atomic physics. Towards this goal, as important as engineering new states of matter is the need to develop new techniques to probe these systems. I first describe our work on realizing Bragg scattering of infrared light from ultracold...

We present PYATB, a Python package designed for computing band structures and related properties of materials using the ab initio tight-binding Hamiltonian. The Hamiltonian is directly obtained after conducting self-consistent calculations with first-principles packages numerical atomic orbital (NAO) bases, such as ABACUS. comprises three modules: Bands, Geometric, Optical. In Bands module, one...

In this review we demonstrate how the algebraic Bethe ansatz is used for the calculation of the energy spectra and form factors (operator matrix elements in the basis of Hamiltonian eigenstates) in exactly solvable quantum systems. As examples we apply the theory to several models of current interest in the study of BoseEinstein condensates, which have been successfully created using ultracold ...

In this paper we study Multiple periodic solutions for a class of non-autonomous and convex Hamiltonian systems and we investigate use some properties of Ekeland index.