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Herein, we report an effective method for the generation of radio-frequency (RF) sidebands in an electro-optic modulator for the simultaneous magneto-optical trapping of two isotopes. This is achieved by switching the RF signals alternately, which suppresses the generation of unwanted frequency signals and improves the laser power per sideband. The generated sidebands are successfully applied to a dual-rubidium-isotope magneto-optical trap (MOT), which results in an increased number of trapped atoms. This simple, flexible, and robust technique can be implemented in experiments that require a large number of atoms in multiple-isotope MOTs and for various applications. [ABSTRACT FROM AUTHOR]

Energy levels, wavelengths, lifetimes, and hyperfine structure constants for the isotopes of the first and second spectra of radium, Ra I and Ra II, have been compiled. Wavelengths and wavenumbers are tabulated for 226Ra and for other Ra isotopes. Isotope shifts and hyperfine structure constants of even and odd-A isotopes of neutral radium atom and singly ionized radium are included. Experimental lifetimes of the states for both neutral and ionic Ra are also added, where available. The information is beneficial for present and future experiments aimed at different physics motivations using neutral Ra and singly ionized Ra. [ABSTRACT FROM AUTHOR]

In this paper, we investigate light shifts of heavy alkaline earth elements barium (Ba) and radium (Ra), which are interesting for optical lattice clocks and for permanent electric dipole moment searches. Detailed knowledge is required in the design of efficient loading of atoms from a magneto-optical trap into an optical dipole trap, to facilitate Doppler cooling while trapping and to achieve longer lifetimes of the trapped atoms with reduced heating rates. The wavelength dependence of light shifts of the ns2 1S0 ground state, the nsnp 3P1 and ns(n − 1)d 1D2 excited states in barium (n = 6) and the n s2 1S0 ground state, the nsnp 3P1 and ns(n − 1)d 3D2 excited states in radium (n = 7) are calculated. Several magic wavelengths in the visible and infrared regions accessible with commercial lasers for optical dipole trapping of Ba and Ra are identified. [ABSTRACT FROM AUTHOR]

First laser spectroscopic measurements of the 6s5d3D1-6s6p1P1 and 6s5d3D2-6s6p1P1 transitions in several isotopes of atomic barium have been performed. The hyperfine structure of these transitions was optically resolved and isotope shifts for even and odd isotopes were determined. The isotope shifts show a deviation from their expected behavior for odd isotopes in an analysis based on King-plots. This observation puts atomic structure calculations at test because available theories do not predict this. A profound understanding of the wavefunctions for heavy alkaline earth systems like barium (Ba) and radium (Ra) is essential for a theoretical evaluation of their sensitivity to fundamental symmetry breaking effects such as they could be observed, e.g., through permanent electric dipole moments. Further the absolute frequency of the 6s2 1S0-6s6p3P1 intercombination line in 138Ba was determined to be 12 636.6232(1) cm-1. [ABSTRACT FROM AUTHOR]

At KVI the technical structures for the TRI μP facility are nearly all in place. The aim of the project is to use radioactive ions to study fundamental interactions and symmetries. We will measure β-recoil correlations in nuclear β decay. There the V,A structure of the Weak interaction may be violated. The second line of research is the search for a permanent electric dipole moment in Ra, with a magnitude forbidden by the Standard Model. By trapping these radioactive nuclei in atom traps a pure sample that can be manipulated facilitates these searches. The TRI μP facility consists of a production target and magnetic separator on the high energy side and a Radio-Frequency Quadrupole (RFQ) cooler and buncher on the low energy side. An ion catcher stops the fast product nuclides and transport them into the RFQ cooler. New technological approaches were implemented for several of these devices. [ABSTRACT FROM AUTHOR]

We present a viewport for use in ultrahigh vacuum (UHV) based upon the preflattened solder seal design presented in earlier work [Cox et al., Rev. Sci. Instrum. 74, 3185 (2003)]. The design features significant modifications to improve long term performance. The windows have been leak tested to less than 10-10 atm cm3/s. From atom number measurements in an optical dipole trap loaded from a vapor cell magneto-optical trap inside a vacuum chamber accommodating these viewports, we measure a trap lifetime of 9.5 s suggesting a pressure of around 10-10 Torr limited by background rubidium vapor pressure. We also present a simplified design where the UHV seal is made directly to a vacuum pipe. [ABSTRACT FROM AUTHOR]

Abstract: The hyperfine structure of short-lived trapped 211,209Ra+ ions was investigated by means of laser spectroscopy. The hyperfine structure constants A and B of the level were determined. There is a 2.2 standard deviation difference between the theoretical and the more accurate experimental value for the B coefficient of 211Ra+. These measurements provide a test for the atomic theory required for upcoming experiments on atomic parity violation and atomic clocks. [Copyright &y& Elsevier]