Bulletin of the Lebedev Physics Institute

Measurement of the Isotopic Shift of the S1/2–D5/2 Clock Transition in Monoisotopic Clouds of Strontium Ions

K. K. Trichev, Peter V. Borisyuk, P. A. Cherepanov, Д. О. Трегубов, G. Quintana Acosta

Published Dec 1, 2025• 0 citations

Abstract

Abstract The isotopic shifts of the 5s 2S1/2–5p 2P1/2 cooling transition, the 5p 2P1/2–4d 2D3/2 pumping transition, and the 5s 2S1/2–4d 2D5/2 electroquadrupole transition are measured in monoisotopic clouds of strontium ions: 88Sr+, 86Sr+, and 84Sr+. To the best of our knowledge, the isotopic shift of the clock transition at 674 nm in 84Sr+ is measured for the first time and is found to be 1186.7(7.2) MHz. The obtained experimental data is used to construct a King diagram, which allows the field (F) and mass (K) shift constants to be estimated for the transition at a wavelength of 674 nm. The obtained results can be used to test atomic structure calculations, sympathetic cooling, and quantum algorithms.

DOI: 10.3103/s1068335625604650

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Bulletin of the Lebedev Physics Institute

Measurement of the Isotopic Shift of the S1/2–D5/2 Clock Transition in Monoisotopic Clouds of Strontium Ions

K. K. Trichev, Peter V. Borisyuk, P. A. Cherepanov, Д. О. Трегубов, G. Quintana Acosta

Published Dec 1, 2025• 0 citations

Publisher

Abstract

DOI: 10.3103/s1068335625604650

Related papers

Observation of the hyperfine structure of the 2S1/2−2D5/2 transition in 87Sr+

G. P. Barwood, K. Gao, Patrick Robert Gill +2 more

The hyperfine structure of the ${}^{2}{S}_{1/2}{\ensuremath{-}}^{2}{D}_{5/2}$ quadrupole transition at 674 nm in ${}^{87}{\mathrm{Sr}}^{+}$ has been observed. The ion was confined in a Paul trap and cooled using laser radiation at 422 and 1092 nm. The quadrupole transition was observed by monitoring quantum jumps in the 422-nm fluorescence. The odd isotope of strontium has ``clock'' transitions independent of the first-order Zeeman shift and the ${}^{2}{D}_{5/2}$ state hyperfine structure constants have been determined as ${A}_{{D}_{5/2}}=2.1743(14)\mathrm{MHz}$ and ${B}_{{D}_{5/2}}=49.11(6)\mathrm{MHz}.$ Standard uncertainties have been added in parentheses. These values allow the second-order Zeeman shifts to be calculated. The ${}^{88}{\mathrm{Sr}}^{+}{\ensuremath{-}}^{87}{\mathrm{Sr}}^{+}$ isotope shift for the 674-nm quadrupole transition has been measured to be 247.99(4) MHz.The hyperfine structure of the ${}^{2}{S}_{1/2}{\ensuremath{-}}^{2}{D}_{5/2}$ quadrupole transition at 674 nm in ${}^{87}{\mathrm{Sr}}^{+}$ has been observed. The ion was confined in a Paul trap and cooled using laser radiation at 422 and 1092 nm. The quadrupole transition was observed by monitoring quantum jumps in the 422-nm fluorescence. The odd isotope of strontium has ``clock'' transitions independent of the first-order Zeeman shift and the ${}^{2}{D}_{5/2}$ state hyperfine structure constants have been determined as ${A}_{{D}_{5/2}}=2.1743(14)\mathrm{MHz}$ and ${B}_{{D}_{5/2}}=49.11(6)\mathrm{MHz}.$ Standard uncertainties have been added in parentheses. These values allow the second-order Zeeman shifts to be calculated. The ${}^{88}{\mathrm{Sr}}^{+}{\ensuremath{-}}^{87}{\mathrm{Sr}}^{+}$ isotope shift for the 674-nm quadrupole transition has been measured to be 247.99(4) MHz.

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ISOTOPE SHIFT SPECTROSCOPY OF ULTRACOLD STRONTIUM

Neal C. Pisenti

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Measurement of the 2 S 1 / 2 − 2 D 5 / 2 clock transition in a single 171 Yb + ion

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Isotope shifts of natural Sr+ measured by laser fluorescence in a sympathetically cooled Coulomb crystal

B. Dubost, Romain Dubessy, Benjamin Szymanski +3 more

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arXiv:1402.3390Physical Review AMar 7, 201412 citations

Measurement of the Electric Quadrupole Moment of the 4d D5/22 Level in Sr+88

G. P. Barwood, Helen S. Margolis, Guozheng Huang +2 more

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Physical Review LettersSep 22, 200478 citations

Absolute frequency measurements on the 5 s 5 p 3 P 0 → 5 s 6 d 3 D 1 transition in strontium

Shengnan Zhang, B. S. Tiwari, Sandhya Ganesh +2 more

We report the first absolute frequency measurements for the 5 s 5 p 3 P 0 → 5 s 6 d 3 D 1 transition at 394 nm for all the stable strontium isotopes by utilizing repumping induced spectroscopy in a magneto-optical trap. Absolute transition frequency is measured to be 760524409251(25) kHz for Sr 88 . With reference to Sr 88 , the isotope shifts are measured to be 91052(35), 54600(33), and 51641(28) kHz for Sr 84 , Sr 86 , and Sr 87 , respectively. We calculate the hyperfine constants A and B for the fermionic isotope Sr 87 at kHz level. Furthermore, we perform King plot analysis by combining isotope shifts on the 689-nm transition to our data. Published by the American Physical Society 2024We report the first absolute frequency measurements for the 5 s 5 p 3 P 0 → 5 s 6 d 3 D 1 transition at 394 nm for all the stable strontium isotopes by utilizing repumping induced spectroscopy in a magneto-optical trap. Absolute transition frequency is measured to be 760524409251(25) kHz for Sr 88 . With reference to Sr 88 , the isotope shifts are measured to be 91052(35), 54600(33), and 51641(28) kHz for Sr 84 , Sr 86 , and Sr 87 , respectively. We calculate the hyperfine constants A and B for the fermionic isotope Sr 87 at kHz level. Furthermore, we perform King plot analysis by combining isotope shifts on the 689-nm transition to our data. Published by the American Physical Society 2024

arXiv:2306.11082Physical Review ResearchNov 5, 20241 citation

The hyperfine structure of the ${}^{2}{S}_{1/2}{\ensuremath{-}}^{2}{D}_{5/2}$ quadrupole transition at 674 nm in

{}^{87}{\mathrm{Sr}}^{+}

has been observed. The ion was confined in a Paul trap and cooled using laser radiation at 422 and 1092 nm. The quadrupole transition was observed by monitoring quantum jumps in the 422-nm fluorescence. The odd isotope of strontium has ``clock'' transitions independent of the first-order Zeeman shift and the

{}^{2}{D}_{5/2}

state hyperfine structure constants have been determined as

{A}_{{D}_{5/2}}=2.1743(14)\mathrm{MHz}

and

{B}_{{D}_{5/2}}=49.11(6)\mathrm{MHz}.

Standard uncertainties have been added in parentheses. These values allow the second-order Zeeman shifts to be calculated. The ${}^{88}{\mathrm{Sr}}^{+}{\ensuremath{-}}^{87}{\mathrm{Sr}}^{+}$ isotope shift for the 674-nm quadrupole transition has been measured to be 247.99(4) MHz.

Spectroscopy of the 411-nm transition in

{}^{171}{\mathrm{Yb}}^{+}

has been performed and the feasibility of its use as an optical frequency standard has been demonstrated. The

{}^{2}{S}_{1/2}(F=0, {m}_{F}=0){--}^{2}{D}_{5/2}(F=2, {m}_{F}=0)

frequency, at zero-magnetic field, has been measured to be 729 487 779 566(153) kHz. This transition is free from the first-order Zeeman shift and has a measured second-order shift of +0.38(8) Hz/(\ensuremath{\mu}

{\mathrm{T})}^{2}

. In addition, the hyperfine structure of the

{}^{2}{D}_{5/2}

level has been deduced by driving the other hyperfine components of the 411-nm transition, showing it to be inverted. The

{}^{2}{D}_{5/2}

hyperfine splitting, measured to be -191(2) MHz, implies an A factor of -63.6(7) MHz. These data taken in conjunction with previous work yield an isotope shift of ${\ensuremath{\nu}}_{171}\ensuremath{-}{\ensuremath{\nu}}_{172}=+1317.1(1.3)\mathrm{MHz}$ for this transition between the 171 and 172 isotopes.

{10}^{3}

{10}^{4}

laser-cooled

{\mathrm{Sr}}^{+}

ions. The isotope shifts are extracted from the experimental spectra by fitting the data with the analytical solution of the optical Bloch equations describing a three-level atom interacting with two laser beams. This technique allowed us to increase the precision with respect to previously reported data obtained by optogalvanic spectroscopy or fast atomic-beam techniques. The results for the $5s\phantom{\rule{0.16em}{0ex}}{\phantom{\rule{0.16em}{0ex}}}^{2}{S}_{1/2}\ensuremath{\rightarrow}5p\phantom{\rule{0.16em}{0ex}}{\phantom{\rule{0.16em}{0ex}}}^{2}{P}_{1/2}$ transition are ${\ensuremath{\nu}}_{88}\ensuremath{-}{\ensuremath{\nu}}_{84}=+378(4)$ MHz and ${\ensuremath{\nu}}_{88}\ensuremath{-}{\ensuremath{\nu}}_{86}=+170(3)$ MHz, in agreement with previously reported measurements. In the case of the previously unexplored $4d\phantom{\rule{0.16em}{0ex}}{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{3/2}\ensuremath{\rightarrow}5p\phantom{\rule{0.16em}{0ex}}{\phantom{\rule{0.16em}{0ex}}}^{2}{P}_{1/2}$ transition we find ${\ensuremath{\nu}}_{88}\ensuremath{-}{\ensuremath{\nu}}_{84}=\ensuremath{-}828(4)$ MHz and ${\ensuremath{\nu}}_{88}\ensuremath{-}{\ensuremath{\nu}}_{86}=\ensuremath{-}402(2)$ MHz. These results provide more data for stringent tests of theoretical calculations of the isotope shifts of alkali-metal-like atoms. Moreover, they simplify the identification and the addressing of

{\mathrm{Sr}}^{+}

isotopes for ion frequency standards or quantum-information-processing applications in the case of multi-isotope ion strings.