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Precision Measurement of the Lifetime of the 3d D_{5/2} state in 40Ca+

P. A. Barton·C. J. S. Donald·D. M. Lucas·D. A. Stevens·A. M. Steane·D. N. Stacey
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Abstract

We report a measurement of the lifetime of the 3d 2D_{5/2} metastable level in 40Ca+, using quantum jumps of a single cold calcium ion in a linear Paul trap. The 4s S_{1/2} - 3d D_{5/2} transition is significant for single-ion optical frequency standards, astrophysical references, and tests of atomic structure calculations. We obtain tau = 1.168 +- 0.007 s from observation of nearly 64,000 quantum jumps during approximately 32 hours. Our result is more precise and significantly larger than previous measurements. Experiments carried out to quantity systematic effects included a study of a previously unremarked source of systematic error, namely excitation by the broad background of radiation emitted by a semiconductor diode laser. Combining our result with atomic structure calculations yields 1.20 +- 0.01 s for the lifetime of 3d D_{3/2}. We also use quantum jump observations to demonstrate photon anti-bunching, and to estimate background pressure and heating rates in the ion trap.

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P. A. Barton, C. J. S. Donald, D. M. Lucas, D. A. Stevens, A. M. Steane, D. N. Stacey. 2000-02-15. Precision Measurement of the Lifetime of the 3d D_{5/2} state in 40Ca+. https://doi.org/10.1103/physreva.62.032503

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