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Photoionization and Photoelectric Loading of Barium Ion Traps

A. V. Steele·L. R. Churchill·P. F. Griffin·M. S. Chapman
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Abstract

Simple and effective techniques for loading barium ions into linear Paul traps are demonstrated. Two-step photoionization of neutral barium is achieved using a weak intercombination line (6s2 1S0 <-> 6s6p 3P1, 791 nm) followed by excitation above the ionization threshold using a nitrogen gas laser (337 nm). Isotopic selectivity is achieved by using a near Doppler-free geometry for excitation of the triplet 6s6p 3P1 state. Additionally, we report a particularly simple and efficient trap loading technique that employs an in-expensive UV epoxy curing lamp to generate photoelectrons.

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A. V. Steele, L. R. Churchill, P. F. Griffin, M. S. Chapman. 2007-03-22. Photoionization and Photoelectric Loading of Barium Ion Traps. https://doi.org/10.1103/physreva.75.053404

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