Abstract Trapping and cooling of Sr + isotope ions by an all-diode-laser system has been demonstrated in order to develop a novel mass spectrometric technique in combination with ion trap-laser cooling. First, we constructed external cavity diode lasers and associated stabilization apparatus for laser cooling of Sr + ions. The transition frequencies confirmed by optogalvanic spectroscopy enabled successful cooling of 88 Sr + ions. An image of two trapped ions has been captured by CCD camera. Minor isotopes, 84 Sr + and 86 Sr + , were also cooled and trapped. From an analysis of the observed spectra of a string crystal of each isotope, the isotope shifts of the cooling transition (5s 2 S 1/2 → 5p 2 P 1/2 ) of Sr + ions were determined to be +371(8) MHz for Δν 84–88 and +169(8) MHz for Δν 86–88 . In the case of the repumping transition (4d 2 D 3/2 → 5p 2 P 1/2 ), Δν 84–88 and Δν 86–88 were measured to be −833(6) and −400(5) MHz, respectively. These values are in good agreement with previously reported values.Abstract Trapping and cooling of Sr + isotope ions by an all-diode-laser system has been demonstrated in order to develop a novel mass spectrometric technique in combination with ion trap-laser cooling. First, we constructed external cavity diode lasers and associated stabilization apparatus for laser cooling of Sr + ions. The transition frequencies confirmed by optogalvanic spectroscopy enabled successful cooling of 88 Sr + ions. An image of two trapped ions has been captured by CCD camera. Minor isotopes, 84 Sr + and 86 Sr + , were also cooled and trapped. From an analysis of the observed spectra of a string crystal of each isotope, the isotope shifts of the cooling transition (5s 2 S 1/2 → 5p 2 P 1/2 ) of Sr + ions were determined to be +371(8) MHz for Δν 84–88 and +169(8) MHz for Δν 86–88 . In the case of the repumping transition (4d 2 D 3/2 → 5p 2 P 1/2 ), Δν 84–88 and Δν 86–88 were measured to be −833(6) and −400(5) MHz, respectively. These values are in good agreement with previously reported values.

Japanese Journal of Applied PhysicsMay 23, 201711 citations

Laser cooling and imaging of individual radioactive Sr+90 ions

Kyunghun Jung, Yoshihiro Iwata, Masabumi Miyabe +4 more

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

Laser cooling, trapping and spectroscopy of calcium isotopes

A. K. Mollema

Jan 1, 20082 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.