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arXiv · 1501.01562

Ground-state cooling of a trapped ion using long-wavelength radiation

S. Weidt·J. Randall·S. C. Webster·E. D. Standing·A. Rodriguez·A. E. Webb·B. Lekitsch·W. K. Hensinger
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Abstract

We demonstrate ground-state cooling of a trapped ion using radio-frequency (RF) radiation. This is a powerful tool for the implementation of quantum operations, where RF or microwave radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\%. After preparing in the vibrational ground state, we demonstrate motional state engineering by driving Rabi oscillations between the n=0 and n=1 Fock states. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

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S. Weidt, J. Randall, S. C. Webster, E. D. Standing, A. Rodriguez, A. E. Webb, B. Lekitsch, W. K. Hensinger. 2015-01-07. Ground-state cooling of a trapped ion using long-wavelength radiation. https://doi.org/10.1103/physrevlett.115.013002

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