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Updated: Aug 4, 2026

Automated 90Sr Separation and Preconcentration in a Lab-on-Valve System at Ppq Level
Published on: June 6, 2018
Measurement of the electric quadrupole moment of the 4d2D5/2 level in 88Sr+
G P Barwood1, H S Margolis, G Huang
1National Physical Laboratory (NPL), Teddington, Middlesex TW11 0LW, United Kingdom. Geoffrey.Barwood@npl.co.uk
Abstract:
The quadrupole moment of the 4d (2)D(5/2) level in 88Sr+ has been measured to be 2.6(3)ea(2)(0), where a(0) is the Bohr radius and e the elementary charge. A single laser-cooled strontium ion was confined in an end cap trap with a variable dc quadrupole potential, and measurements were made on the 5s (2)S(1/2)-4d (2)D(5/2) transition at 674 nm using a femtosecond optical frequency comb. This work shows that measurements of the unperturbed 88Sr+ transition frequency with sub-Hz uncertainty are possible and is important in understanding the reproducibility of ion trap optical frequency standards.
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