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Spectroscopy of a synthetic trapped ion qubit

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 نشر من قبل David Hucul
 تاريخ النشر 2017
  مجال البحث فيزياء
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$^{133}text{Ba}^+$ has been identified as an attractive ion for quantum information processing due to the unique combination of its spin-1/2 nucleus and visible wavelength electronic transitions. Using a microgram source of radioactive material, we trap and laser-cool the synthetic $A$ = 133 radioisotope of barium II in a radio-frequency ion trap. Using the same, single trapped atom, we measure the isotope shifts and hyperfine structure of the $6^2 text{P}_{1/2}$ $leftrightarrow$ $6^2 text{S}_{1/2}$ and $6^2 text{P}_{1/2}$ $leftrightarrow$ $5^2 text{D}_{3/2}$ electronic transitions that are needed for laser cooling, state preparation, and state detection of the clock-state hyperfine and optical qubits. We also report the $6^2 text{P}_{1/2}$ $leftrightarrow$ $5^2 text{D}_{3/2}$ electronic transition isotope shift for the rare $A$ = 130 and 132 barium nuclides, completing the spectroscopic characterization necessary for laser cooling all long-lived barium II isotopes.

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