Related papers: Van-der-Waals potentials of paramagnetic atoms
Atoms deposited on two-dimensional (2D) electronic materials, such as graphene, can exhibit unconventional many-body correlations, not accessible in other settings. All of these are driven by van der Waals forces: between the atoms…
The description of the molecular solid phase of O$_2$, especially its ground-state antiferromagnetic insulating phase, is known to be quite unsatisfactory within the conventional local and semilocal density functional approximations used in…
We study the two-body bound states of a model Hamiltonian that describes the interaction between two field-oriented dipole moments. This model has been used extensively in many-body physics of ultracold polar molecules and magnetic atoms,…
Mutual Coulomb interactions between electrons lead to a plethora of interesting physical and chemical effects, especially if those interactions involve many fluctuating electrons over large spatial scales. Here, we identify and study in…
This chapter deals with atom-wall interaction occurring in the "long-range" regime (typical distances: 1-1000 nm), when the electromagnetic fluctuations of an isolated atom are modified by the vicinity with a surface. Various regimes of…
A four-vector field in flat space-time, satisfying a gauge-invariant set of second-order differential equations, is considered as a unified field. The model variational principle corresponds to the general covariance idea and gives rise to…
In this paper we give an application of Dalgarno-Lewis method, the latter not usually taught in quantum mechanics courses. This is very unfortunate since this method allows to bypass the sum over states appearing in the usual perturbation…
Theories for the effective polarisability of a small particle in a medium are presented using different levels of approximation: we consider the virtual cavity, real cavity and the hard-sphere models as well as a continuous interpolation of…
We study a two dimensional electron system in a parabolic confining potential and constant magnetic field for the case of harmonic electron-electron interaction. We present analytic results for the electrochemical potential versus magnetic…
A model of interacting two dimensional electrons near a Van Hove singularity is studied, using renormalization group techniques. In hole doped systems, the chemical potential is found to be pinned near the singularity, when the…
The response of matter to fields underlies the physical sciences, from particle physics to astrophysics, and from chemistry to biophysics. We observe an atom's response to an electric quadrupole field to second- and higher orders; this…
Vacuum polarization corrections to the energy levels of bound electrons are calculated using a perturbative path integral formalism. We apply quantum electrodynamics in a framework which treats the strong binding nuclear field to all…
We study the ground state of a large bosonic system trapped in a symmetric double-well potential, letting the distance between the two wells increase to infinity with the number of particles. In this context, one should expect an…
We present a new perturbation theory for quantum mechanical energy eigenstates when the potential equals the sum of two localized, but not necessarily weak potentials $V_{1}(\vec{r})$ and $V_{2}(\vec{r})$, with the distance $L$ between the…
In this letter we derive an expression for the force acting on a small (still macroscopic) particle in the field of the quantized electromagnetic radiation in any arbitrary quantum state. This result unifies in one simple formula all known…
The science and applications of electronics and optoelectronics have been driven for decades by progress in growth of semiconducting heterostructures. Many applications in the infrared and terahertz frequency range exploit transitions…
In this paper, a model by which we study the interaction between a motional three-level atom and two-mode field injected simultaneously in a bichromatic cavity is considered; the three-level atom is assumed to be in a $\Lambda$-type…
We have computed the widely neglected first-order interaction between neutral atoms. At interatomic separations typical of condensed media, it is nearly equal to the 1/r^6 second-order London energy inferred from interactions in gasses. Our…
The van der Waals coefficients for the alkali-metal atoms from Na to Fr interacting in their ground states, are calculated using relativistic ab initio methods. The accuracy of the calculations is estimated by also evaluating atomic static…
Within density-functional theory, perturbation theory~(PT) is the state-of-the-art formalism for assessing the response to homogeneous electric fields and the associated material properties, e.g., polarizabilities, dielectric constants, and…