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Photoionization of strontium for trapped-ion quantum information processing

K. Vant·J. Chiaverini·W. Lybarger·D. J. Berkeland
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Abstract

We report a demonstration of simple and effective loading of strontium ions into a linear radio frequency Paul trap using photoionization. The ionization pathway is 5s2 1S0 -- 5s5p 1P1 -- 5p2 1D2, and the 5p2 1D2 final state is auto-ionizing. Both transitions are driven using diode lasers: a grating-stabilized 922 nm diode doubled in a single pass through potassium niobate to 461 nm and a bare diode at 405 nm. Using this technique, we have reduced the background pressure during the ion loading process by a factor of 2 compared to the conventional technique of electron bombardment. Initial ion temperatures are low enough that the ions immediately form crystals. It is also possible to observe the trapping region with a CCD camera during ion creation, allowing specific ion number loading with high probability.

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K. Vant, J. Chiaverini, W. Lybarger, D. J. Berkeland. 2006-07-07. Photoionization of strontium for trapped-ion quantum information processing. https://arxiv.org/abs/quant-ph/0607055

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