Dark-state suppression and optimization of laser cooling and fluorescence in a trapped alkaline-earth-metal single ion

Abstract

We study the formation and destabilization of dark states in a single trapped 88Sr+ ion caused by the cooling and repumping laser fields required for Doppler cooling and fluorescence detection of the ion. By numerically solving the time-dependent density matrix equations for the eight-level system consisting of the sublevels of the 5s 2S1/2, 5p 2P1/2, and 4d 2D3/2 states, we analyze the different types of dark states and how to prevent them in order to maximize the scattering rate, which is crucial for both the cooling and the detection of the ion. The influence of the laser linewidths and ion motion on the scattering rate and the dark resonances is studied. The calculations are then compared with experimental results obtained with an endcap ion trap system located at the National Research Council of Canada and found to be in good agreement. The results are applicable also to other alkaline earth ions and isotopes without hyperfine structure.

References in corpus (2)

• Destabilization of dark states and optical spectroscopy in Zeeman-degenerate atomic systems
• Blackbody-radiation shift in a 88Sr+ ion optical frequency standard

Cited by in corpus (6)

• Evaluation of a ${}^{88}$Sr${}^{+}$ optical clock with a direct measurement of the blackbody radiation shift and determination of the clock frequency
• Broadband, unpolarized repumping and clearout light sources for Sr${}^{+}$ single-ion clocks
• High-Accuracy Determination of Paul-Trap Stability Parameters for Electric-Quadrupole-Shift Prediction
• Unpolarized, incoherent repumping light for prevention of dark states in a trapped and laser-cooled single ion
• Broadband lasers for photo-ionization and repumping of trapped ions
• Competition between Factors Determining Bright versus Dark Atomic States within a Laser Mode