Engineering topics

Dzuba, V A

Publications and source records attributed to Dzuba, V A.

9 records

DOE OSTI2011

Electron-Hole Transitions in Multiply Charged Ions for Precision Laser Spectroscopy and Searching for Variations in {alpha}

We consider transitions of electron holes (vacancies in otherwise filled shells of atomic systems) in multiply charged ions that, due to level crossing of the holes, have frequencies within the range of optical atomic clocks. Strong E1 transitions provide options for laser cooling and trapping, while narrow transitions can be used for high-precision spectroscopy and tests of fundamental physics. We show that hole transitions can have extremely high sensitivity to {alpha} variation and propose candidate transitions that have much larger {alpha} sensitivities than any previously seen in atomic systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2011

Calculation of nuclear-spin-dependent parity nonconservation in s-d transitions of Ba{sup +}, Yb{sup +}, and Ra{sup +} ions

We use correlation potential and many-body perturbation theory techniques to calculate spin-independent and nuclear-spin-dependent parts of the parity nonconserving amplitudes of the transitions between the 6s{sub 1/2} ground state and the 5d{sub 3/2} excited state of Ba{sup +} and Yb{sup +} and between the 7s{sub 1/2} ground state and the 6d{sub 3/2} excited state of Ra{sup +}. The results are presented in a form convenient for the extracting of the constants of nuclear-spin-dependent interaction (such as, e.g., anapole moment) from the measurements.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2011

Calculation of parity nonconservation in neutral ytterbium

We use configuration interaction and many-body perturbation theory techniques to calculate spin-independent and spin-dependent parts of the parity-nonconserving amplitudes of the transitions between the 6s{sup 2} {sup 1}S{sub 0} ground state and the 6s5d {sup 3}D{sub 1} excited state of {sup 171}Yb and {sup 173}Yb. The results are presented in a form convenient for extracting spin-dependent interaction constants (such as anapole moment) from the measurements.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2011

Dynamic polarizabilities and magic wavelengths for dysprosium

We theoretically study dynamic scalar polarizabilities of the ground and select long-lived excited states of dysprosium, a highly magnetic atom recently laser cooled and trapped. We demonstrate that there is a set of magic wavelengths of the unpolarized lattice laser field for each pair of states, which includes the ground state and one of these excited states. At these wavelengths, the energy shift due to laser field is the same for both states, which can be useful for resolved sideband cooling on narrow transitions and precision spectroscopy. We present an analytical formula that, near resonances, allows for the determination of approximate values of the magic wavelengths without calculating the dynamic polarizabilities of the excited states.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2011

Possibility of Stark-insensitive cotrapping of two atomic species in optical lattices

Much effort has been devoted to removing differential Stark shifts for atoms trapped in specially tailored ''magic'' optical lattices, but thus far work has focused on a single trapped atomic species. In this work, we extend these ideas to include two atomic species sharing the same optical lattice. We show qualitatively that, in particular, scalar J=0 divalent atoms paired with nonscalar state atoms have the necessary characteristics to achieve such Stark shift cancellation. We then present numerical results on ''magic'' trapping conditions for {sup 27}Al paired with {sup 87}Sr, as well as several other divalent atoms.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2010

Hyperfine-mediated static polarizabilities of monovalent atoms and ions

We apply relativistic many-body methods to compute static differential polarizabilities for transitions inside the ground-state hyperfine manifolds of monovalent atoms and ions. Knowledge of this transition polarizability is required in a number of high-precision experiments, such as microwave atomic clocks and searches for CP-violating permanent electric dipole moments. While the traditional polarizability arises in the second order of interaction with the externally applied electric field, the differential polarizability involves an additional contribution from the hyperfine interaction of atomic electrons with nuclear moments. We derive formulas for the scalar and tensor polarizabilities including contributions from magnetic dipole and electric quadrupole hyperfine interactions. Numerical results are presented for Al, Rb, Cs, Yb{sup +}, Hg{sup +}, and Fr.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2010

Enhanced Laboratory Sensitivity to Variation of the Fine-Structure Constant using Highly Charged Ions

We study atomic systems that are in the frequency range of optical atomic clocks and have enhanced sensitivity to potential time variation of the fine-structure constant {alpha}. The high sensitivity is due to coherent contributions from three factors: high nuclear charge Z, high ionization degree, and significant differences in the configuration composition of the states involved. Configuration crossing keeps the frequencies in the optical range despite the large ionization energies. We discuss a few promising examples that have the largest {alpha} sensitivities seen in atomic systems.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2010

Axio-electric effect

Using the relativistic Hartree-Fock approximation, we calculate the rates of atomic ionization by absorption of axions of the energies up to 100 keV and for an arbitrary value of the axion mass. We present numerical results for atoms used in the low radioactive background searches of dark matter (e.g., Ar, Ge, and Xe), as well as an analytical formula which fits numerical calculations for the absorption cross sections and can be applied to other atoms, molecules, and condensed matter systems. Using the cross sections for the axio-electric effect, we derive the counting rates induced by solar axions and set limits on the axion coupling constants.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2010

Relativistic many-body calculation of low-energy dielectronic resonances in Be-like carbon

We apply the relativistic configuration-interaction method coupled with the many-body perturbation theory (CI+MBPT) to describe low-energy dielectronic recombination. We combine the CI+MBPT approach with the complex rotation method (CRM) and compute the dielectronic recombination spectrum for Li-like carbon, which recombines into Be-like carbon. We demonstrate the utility and evaluate the accuracy of this newly developed CI+MBPT+CRM approach by comparing our results with the results of the previous high-precision study of the Ciii system [Mannervik et al., Phys. Rev. Lett. 81, 313 (1998)].

74 ATOMIC AND MOLECULAR PHYSICS↗