We have developed an apparatus integrating resonance-ionization, ion-trap, and laser-cooling techniques for an ultratrace radioactive isotope $^{90}\mathrm{Sr}$ analysis. Trapped $^{90}\mathrm{Sr}^{+}$ isotope ions were laser cooled, and their $4d\phantom{\rule{0.16em}{0ex}}^{2}D_{3/2}\ensuremath{\rightarrow}5p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ transition isotope shift was experimentally measured to be $\ensuremath{-}281(17)$ MHz by comparing individual spectra of $^{88}\mathrm{Sr}^{+}$ and $^{90}\mathrm{Sr}^{+}$ ions. Crystallization of $^{90}\mathrm{Sr}^{+}$ was carried out using the resonance frequency value confirmed in our experiment, and then $^{90}\mathrm{Sr}^{+}$ individual ions were successfully observed.We have developed an apparatus integrating resonance-ionization, ion-trap, and laser-cooling techniques for an ultratrace radioactive isotope $^{90}\mathrm{Sr}$ analysis. Trapped $^{90}\mathrm{Sr}^{+}$ isotope ions were laser cooled, and their $4d\phantom{\rule{0.16em}{0ex}}^{2}D_{3/2}\ensuremath{\rightarrow}5p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ transition isotope shift was experimentally measured to be $\ensuremath{-}281(17)$ MHz by comparing individual spectra of $^{88}\mathrm{Sr}^{+}$ and $^{90}\mathrm{Sr}^{+}$ ions. Crystallization of $^{90}\mathrm{Sr}^{+}$ was carried out using the resonance frequency value confirmed in our experiment, and then $^{90}\mathrm{Sr}^{+}$ individual ions were successfully observed.

Physical Review AOct 30, 201712 citations

We have developed an apparatus integrating resonance-ionization, ion-trap, and laser-cooling techniques for an ultratrace radioactive isotope

^{90}\mathrm{Sr}

analysis. Trapped

^{90}\mathrm{Sr}^{+}

isotope ions were laser cooled, and their $4d\phantom{\rule{0.16em}{0ex}}^{2}D_{3/2}\ensuremath{\rightarrow}5p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ transition isotope shift was experimentally measured to be $\ensuremath{-}281(17)$ MHz by comparing individual spectra of

^{88}\mathrm{Sr}^{+}

and

^{90}\mathrm{Sr}^{+}

ions. Crystallization of

^{90}\mathrm{Sr}^{+}

was carried out using the resonance frequency value confirmed in our experiment, and then

^{90}\mathrm{Sr}^{+}

individual ions were successfully observed.