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arXiv · 1412.0782

Sympathetic cooling of molecular ion motion to the ground state

Rene Rugango·James E. Goeders·Thomas H. Dixon·John M. Gray·Ncamiso Khanyile·Gang Shu·Robert J. Clark·Kenneth R. Brown
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Abstract

We demonstrate sympathetic sideband cooling of a $^{40}$CaH$^{+}$ molecular ion co-trapped with a $^{40}$Ca$^{+}$ atomic ion in a linear Paul trap. Both axial modes of the two-ion chain are simultaneously cooled to near the ground state of motion. The center of mass mode is cooled to an average quanta of harmonic motion $\overline{n}_{\mathrm{COM}} = 0.13 \pm 0.03$, corresponding to a temperature of $12.47 \pm 0.03 ~\mu$K. The breathing mode is cooled to $\overline{n}_{\mathrm{BM}} = 0.05 \pm 0.02$, corresponding to a temperature of $15.36 \pm 0.01~\mu$K.

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Rene Rugango, James E. Goeders, Thomas H. Dixon, John M. Gray, Ncamiso Khanyile, Gang Shu, Robert J. Clark, Kenneth R. Brown. 2014-12-02. Sympathetic cooling of molecular ion motion to the ground state. https://doi.org/10.1088/1367-2630/17/3/035009

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