Cavity sideband cooling of a single trapped ion. D. R. Leibrandt, J. Labaziewicz, V. Vuletic, and I. L. Chuang, submitted to Phys. Rev. Lett (5/2009).
Fig. 1. Cavity cooling dynamics. The ion is sideband cooled to the three-dimensional motional ground
state; a cavity cooling pulse with resonant laser-cavity tuning (green curve), the laser tuned to the blue of the cavity by one trap vibration frequency (cavity heating, blue curve), or the laser tuned to the red of the cavity by one trap vibration frequency (cavity cooling, red curve). The mean number of motional quanta <n> in the z mode is measured. The increase in <n> for the resonant cavity is due to recoil heating by free space scattering, cavity cooling in contrast leads to a steady-state temperature of 22 motional quanta, in spite of the recoil heating.
We report a demonstration and quantitative characterization of one-dimensional cavity cooling of a single trapped 88Sr+ ion in the resolved sideband regime. We measure the spectrum of cavity transitions, the rates of cavity heating and cooling, and the steady-state cooling limit. The cavity cooling dynamics and cooling limit of 22.5(3) motional quanta, limited by the moderate coupling between the ion and the cavity, are consistent with a simple model without any free parameters, validating the rate equation model for cavity cooling.
This work is a joint CUA experiment of Chuang’s and Vuletic’s groups.