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Long ground-Rydberg coherence lifetime is interesting for implementing high-fidelity quantum logic gates, many-body physics, and other quantum information protocols. However, the potential formed by a conventional far-off-resonance red-detuned optical-dipole trap (ODT) is usually repulsive for Rydberg atoms, which will result in fast atom loss and low repetition rate of the experimental sequence. These issues can be addressed by a magic ODT. We performed the calculation of ODT's magic detuning for confinement of ground-state and Rydberg-state cesium atoms with the same potential well. We used a sum-over-states method to calculate the dynamic polarizabilities of 6S1/2 ground state and highly-excited (nS1/2 and nP3/2) Rydberg state of cesium atoms, and identify corresponding magic detuning for optical wavelengths in the range of 850–1950 nm. We estimated the trapping lifetime of cesium Rydberg atoms confined in the magic ODT by including different dissipative mechanisms. Furthermore, we have experimentally realized an 1879.43 nm single-frequency laser system with a watt-level output power for setting up the magic ODT for 6S1/2 ground-state and 84P3/2 Rydberg-state cesium cold atoms. [ABSTRACT FROM AUTHOR]

Knowledge of optical effects accompanying hypersonic flight conditions is of critical importance to ensure reliable operation of on-board optical instrumentation. This paper presents results of calculations of scalar polarizability dependence on vibrational non-equilibrium in molecular nitrogen and oxygen. The non-equilibrium effects are evaluated on the basis of a semi-classical model for the molecular polarizability. It is shown that, depending on the vibrational and translational populations, changes in the scalar polarizability in excess of normal density and temperature scaling can be around 1%–5% at moderate gas temperatures and around 10% at high temperatures. The model was applied to predict the polarizability for non-equilibrium states in a nitrogen plasma formed by a single nanosecond pulse with different rise times. [ABSTRACT FROM AUTHOR]

A pure topological effect on the radiative processes of an inertial atom due to the compactification in a spatial dimension is investigated. The atom is locally coupled to a bath of fluctuating quantum electromagnetic field in the compactified Minkowski spacetime. Specifically, using the perturbation theory we calculate the atomic transition rates both for a static atom and for a uniformly moving atom along the compactified or non-compactified spatial direction. As a rule, the atomic transition rates depend much on the circumference of the compactified dimension and the atomic polarizability. Remarkably, for inertial atoms moving at different constant velocities along the compactified direction, their transition rates can be quite different, in sharp contrast with the case in the free Minkowski spacetime. [ABSTRACT FROM AUTHOR]

The ground-state permanent dipole moments (PDMs) and molecular dipole polarizabilities (DPs) of open-shell alkaline-earth monofluorides, and atomic DPs of alkaline-earth- and fluorine atoms are reported at the Kramers-restricted configuration interaction level of theory limited to single and double excitations (KRCISD), using the finite-field approach. Sufficiently large basis sets such as quadrupole-zeta (QZ) and augmented-QZ basis sets together with the generalized active space technique is employed to carry out the field-dependent energy calculations at the KRCISD level. The PDMs and the components of DPs are extracted from the linear- and quadratic fit of energies against perturbative electric field, respectively. Accuracy of the present calculations for the electronic properties is examined by comparison with the measurements and calculations where ever available. [ABSTRACT FROM AUTHOR]

Resonant radiation force exerted on a semiconductor quantum well nanostructure (QWNS) from intersubband transition of electrons is investigated by taking the nonlocal coupling between the polarizability of electrons and applied optical fields into account for two kinds of polarized states. The numerical results show the spatial nonlocality of optical response can induce the spectral peak position of the exerted force to have a blueshift, which is sensitively dependent on the polarized state and the QWNS width. It is also demonstrated that resonant radiation force is controllable by the polarization and incident directions of applied light waves. This work provides effective methods for controlling optical force and manipulating nano-objects, and observing radiation forces in experiment. This nonlocal interaction mechanism can also be used to probe and predominate internal quantum properties of nanostructures, and to manipulate collective behavior of nano-objects. [ABSTRACT FROM AUTHOR]

We study static the electric field and electromagnetic waves in dielectric media. In contrast to the standard approach, we use, formulate and solve integral equations for the field. We discuss the case of an electrostatic field of a point charge placed inside a dielectric; the integral equation approach allows us to find and interpret the dielectric constant in terms of molecular polarizability. Next we discuss propagation of electromagnetic waves using the same integral equation approach. We derive the dispersion relation and find the reflection and transmission coefficients at the boundary between the vacuum and the dielectric. The present approach supplements the standard approach based on macroscopic Maxwell equations and contributes to better a understanding of some electromagnetic effects. [ABSTRACT FROM AUTHOR]

Electronic dipole moment and static polarizability functions for some diatomic molecules (H2, N2, O2, NO, OH, CO, CH, HF and HCl) that are important for combustion and atmospheric chemistry are calculated by using ab initio methods over a broad range of internuclear distances. Using the ab initio calculated data on the electric properties and potential energy functions, the effective values of dipole moment and static polarizability as well as the energy levels of these molecules in individual vibrational and rotational states until the dissociation threshold are determined. It is revealed that, for the ground electronic states of molecules under study, the excitation of molecule vibrations can affect the averaged dipole moment and static polarizability substantially, whereas the effect of excitation of the rotational states is less pronounced. [ABSTRACT FROM AUTHOR]

We have measured the frequencies of 24 transitions between Rydberg singlet L = 2–4 levels of zinc in the frequency range 79–285 GHz. The transitions were driven from 4snf 1F3 levels that were excited by two-step laser excitation through 4s4d 1D2. Single-photon 4snf 1F3 4s(n + 2)d 1D2, 4snf 1F3 4s(n + 3)d 1D2, 4snf 1F3 4s(n + 1)g 1G4, and two-photon 4snf 1F3 4s(n + 1)f 1F3 series for principal quantum number n = 28–40 were observed. Ritz expansion coefficients in the single-channel quantum defect theory were obtained for D, F and G states by least square fitting analysis of the spectra. An estimate of the dipole polarizability of Zn+ has been obtained. [ABSTRACT FROM AUTHOR]

The static dipole polarizability of metastable states in pionic helium atoms is studied. We use the complex coordinate rotation method to properly take account of the resonant nature of the states. Our calculation shows that the (17, 14) states both in 3He and 4He are not stable due to strong collisional quenching. This explains the absence of signal in the PiHe experiment at the Paul Scherer Institute, Switzerland while studying the (16, 15) (17, 14) transition. [ABSTRACT FROM AUTHOR]

A model for positron binding to polar molecules is considered by combining the dipole potential outside the molecule with a strongly repulsive core of a given radius. Using existing experimental data on binding energies leads to unphysically small core radii for all of the molecules studied. This suggests that electron–positron correlations neglected in the simple model play a large role in determining the binding energy. We account for these by including the polarization potential via perturbation theory and non-perturbatively. The perturbative model makes reliable predictions of binding energies for a range of polar organic molecules and hydrogen cyanide. The model also agrees with the linear dependence of the binding energies on the polarizability inferred from the experimental data (Danielson et al 2009 J. Phys. B: At. Mol. Opt. Phys.42 235203). The effective core radii, however, remain unphysically small for most molecules. Treating molecular polarization non-perturbatively leads to physically meaningful core radii for all of the molecules studied and enables even more accurate predictions of binding energies to be made for nearly all of the molecules considered. [ABSTRACT FROM AUTHOR]

TiO2 and SiO2 are materials with unique importance in materials science. They are often modelled using conventional force fields, but including polarization effects is compulsory for enhancing the accuracy of the simulations. Here we parameterize a force field for the two materials in the framework of the polarizable ion model. The parameterization is performed via a generalized force-fitting methodology using DFT calculations as reference data. We show that it is possible to generate a force field in which the same parameters are used for the oxide ion in both SiO2 and TiO2, and which is able to reproduce accurately the equilibrium structure of their various crystalline polymorphs, as well as glassy silica. [ABSTRACT FROM AUTHOR]

A Ramsey-type interferometer is suggested, employing a cold trapped ion and two time-delayed off-resonant femtosecond laser pulses. The laser light couples to the molecular polarization anisotropy, inducing rotational wavepacket dynamics. An interferogram is obtained from the delay dependent populations of the final field-free rotational states. Current experimental capabilities for cooling and preparation of the initial state are found to yield an interferogram visibility of more than 80%. The interferograms can be used to determine the polarizability anisotropy with an accuracy of about ±2%, respectively ±5%, provided the uncertainty in the initial populations and measurement errors are confined to within the same limits. [ABSTRACT FROM AUTHOR]

Static and dynamic polarizabilities are calculated for the non-relativistic hydrogen molecular ion by solving the three-body Schrödinger equation in perimetric coordinates with the Lagrange-mesh method. The static dipole polarizabilities of the ground-state rotational band are computed for total orbital (or rotational) angular momenta from L = 0 to 39 with an absolute accuracy of about 10−9 au. For L = 0, 1 and 2, slightly less accurate results are also given for the first three vibrational excited levels. For the ground state, dynamic dipole polarizabilities as well as static and dynamic quadrupole polarizabilities are computed. To illustrate the versatility of the method, the static dipole polarizability of the hydrogen molecular ion in a Debye plasma is also determined. [ABSTRACT FROM AUTHOR]