Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1502.07855 · Physical Review A

Lifetime determination of the 5d2 3F2 state in barium using trapped atoms

Subhadeep De, Umakanth Dammalapati, Lorenz Willmann

Published Mar 26, 2015• 1 citation
arXivHTMLPDF

Abstract

Magneto-optically trapped atoms enable the determination of lifetimes of metastable states and higher lying excited states like the $5{d}^{2}{\phantom{\rule{0.28em}{0ex}}}^{3}{F}_{2}$ state in barium. The state is efficiently populated by driving strong transitions from metastable states within the cooling cycle of the barium magneto-optical trap (MOT). The lifetime is inferred from the increase of MOT fluorescence after the transfer of up to $30%$ of the trapped atoms to this state. The radiative decay of the $5{d}^{2}{\phantom{\rule{0.28em}{0ex}}}^{3}{F}_{2}$ state cascades to the cooling cycle of the MOT with a probability of $96.0(7)%$ corresponding to a trap loss of $4.0(7)%$ and its lifetime is determined to $160(10)\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$. This is in good agreement with the theoretically calculated lifetime of $190\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$ [V. A. Dzuba and V. V. Flambaum, J. Phys. B 40, 227 (2007)]. The determined loss of $4.0(7)%$ from the cooling cycle is compared with the theoretically calculated branching ratios. This measurement extends the efficacy of trapped atoms to measure lifetimes of higher, long-lived states and validate the atomic structure calculations of heavy multielectron systems.

DOI
10.1103/physreva.91.032517

Related papers

Magneto-optical trapping of barium

Subhadeep De, Umakanth Dammalapati, Klaus Peter Jungmann +1 more

Laser cooling and trapping of the heavy alkaline-earth-metal element barium has been achieved based on the strong $6{s}^{2}\text{ }{^{1}S}_{0}\text{\ensuremath{-}}6s6p\text{ }{^{1}P}_{1}$ transition. The excited state decays to a large fraction into metastable $D$ states. Two schemes were implemented where three additional laser-driven transitions provide closed cooling cycles. This results in a fraction of 50(20)% of the trapped atoms in one of the metastable states. A total efficiency of $0.4(1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}2}$ for slowing a thermal atomic beam and capturing atoms into a magneto-optical trap was obtained. Trap lifetimes of more than 1.5 s were observed. They are shortened at high laser intensities by three photon photoionization losses. The developed scheme can be transferred to other systems with large leakage from the cooling transition, such as Ra which is interesting for sensitive fundamental symmetry research.

arXiv:0807.4100•Physical Review A•Apr 13, 2009•73 citations

Laser cooling and trapping of barium

Subhadeep De

Laser cooling and trapping of heavy alkaline-earth element barium have been demonstrated for the first time ever. For any possible cycling transition in barium that could provide strong cooling forces, the excited state has a very large branching probability to metastable states. Additional lasers are thus needed to bring the atoms back in to the cooling cycle. In this work barium atoms were efficiently collected in a magneto-optical trap (MOT) by large optical forces from the strong 6s2 1S0 – 6s6p 1P1 transition. Trapping of barium has been achieved using up to seven lasers simultaneously. The properties of the barium MOT were characterized. The efficiency of capturing an atom from a thermal atomic beam into the MOT is 0.4(1) %. The developed scheme is very efficient for collecting atoms. Loss rate mechanisms from the trap were studied by observing the decay of the trap population. Typical lifetimes of the MOT cloud are on the order of one second and are limited mainly due to insufficient repumping of metastable states. The range of velocities from which barium atoms can be captured into the MOT is about 30 m/s. Different laser transitions were employed for repumping barium atoms from the 6s5d 3D1 and the 6s5d 3D2 states. They lead to similar trap populations and lifetimes. The temperature of the cold atomic barium cloud was determined to about 5 mK. Atomic properties of the 5d2 3F2 state were studied with trapped atoms, in particular it's lifetime was determined as 160(10) s. This work has shown a possible scheme to trap atoms with a leaky cooling cycle. Since atoms with such properties are the majority of the elements in the periodic table, the number of optically trapable elements can be significantly enlarged. Of particular high interest is radium, which is chemical homologue to barium. The interest in radium stems from it's high sensitivity to possible nuclear and electron permanent electric dipole moments (EDM's). An EDM violates parity as well as time reversal and is therefore of fundamental importance. Searches for such EDM's are among the main research goals of the recently commissioned TRImP facility at KVI.

•Jan 1, 2008•4 citations

Measurement of the 3s3p P31 lifetime in magnesium using a magneto-optical trap

P. L. Hansen, Kasper T. Therkildsen, Nicola Malossi +6 more

We demonstrate an accurate method for measuring the lifetime of long-lived metastable magnetic states using a magneto-optical trap (MOT). Through optical pumping, the metastable $(3s3p)\text{ }{^{3}P}_{1}$ level is populated in a standard MOT. During the optical pumping process, a fraction of the population is captured in the magnetic quadrupole field of the MOT. When the metastable atoms decay to the $(3{s}^{2})\text{ }{^{1}S}_{0}$ ground state they are recaptured into the MOT. In this system no alternative cascading transition is possible. The lifetime of the metastable level is measured directly as an exponential load time of the MOT. We have experimentally tested our method by measuring the lifetime of the $(3s3p)\text{ }{^{3}P}_{1}$ of $^{24}\text{M}\text{g}$. This lifetime has been measured numerous times previously, but with quite different results. Using our method we find the $(3s3p)\text{ }{^{3}P}_{1}$ lifetime to be $(4.4\ifmmode\pm\else\textpm\fi{}0.2)\text{ }\text{ms}$. Theoretical values point toward a lower value for the lifetime.

Physical Review A•Jun 2, 2008•11 citations

Magneto-optical trap of titanium atoms

Scott Eustice, Jackson Schrott, Anke Stöltzel +4 more

We realize a magneto-optical trap (MOT) of titanium (Ti) atoms, performing laser cooling on the 498 nm transition between the long-lived 3 d 3 ( F 4 ) 4 s a 5 F 5 metastable state and the 3 d 3 ( F 4 ) 4 p y 5 G 6 o excited state. Without the addition of any repumping light, we observe MOTs of the three stable, I = 0 bosonic isotopes, Ti 46 , Ti 48 , and Ti 50 . Up to 8.30 ( 26 ) × 10 5 Ti 48 atoms are trapped at a maximum density of 1.3 ( 4 ) × 10 11 cm − 3 and at a temperature of 90 ( 15 ) µ K . By measuring the decay of the MOT, we constrain the leakage branching ratio of the cooling transition ( ≤ 2.5 × 10 − 6 ) and the two-body loss coefficient ( ≤ 2 × 10 − 10 cm 3 s − 1 ). Our approach to laser cooling Ti can be applied to other transition metals, enabling a significant expansion of the elements that can be laser cooled.

arXiv:2501.05544•Physical Review Research•Apr 8, 2025•5 citations

Analyzing the optical pumping on the 5 s 4 d D 2 1 − 5 s 8 p P 1 1 transition in a magneto-optical trap of Sr atoms

Naohiro Okamoto, T. Aoki, Yoshio Torii

We explore the efficacy of optical pumping on the $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}\text{\ensuremath{-}}5s8p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}$ $(448\phantom{\rule{0.16em}{0ex}}\mathrm{nm})$ transition in a magneto-optical trap (MOT) of Sr atoms. The number of trapped atoms is enhanced by a factor of $12.0(6)$ relative to the case without repumping light, which is six times as large as that obtained using the pumping transition $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}\text{\ensuremath{-}}5s6p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}$ $(717\phantom{\rule{0.16em}{0ex}}\mathrm{nm})$. This enhancement is limited by decay pathways that bypass the $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}$ state, namely $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{1}\ensuremath{\rightarrow}5s5p\phantom{\rule{0.16em}{0ex}}^{3}P_{0}$ and $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{2}\ensuremath{\rightarrow}5s5p\phantom{\rule{0.16em}{0ex}}^{3}P_{2}$, which account for 8% of the total loss of the trapped atoms. We determine the decay rates for the $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{1}$ and $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{2}$ transitions to be $66(6)\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$ and $2.4(2)\ifmmode\times\else\texttimes\fi{}{10}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$, respectively. Furthermore, we experimentally demonstrate, when the trap beam diameter is small, escape of atoms in the $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}$ state, which has a relatively long lifetime of $400\phantom{\rule{0.16em}{0ex}}\textmu{}\mathrm{s}$, becomes a dominant loss mechanism, and that the $448\phantom{\rule{0.16em}{0ex}}\mathrm{nm}$ pumping light effectively suppresses this escape. Our findings will contribute to improved laser cooling and fluorescence imaging in cold strontium atom platforms, such as quantum computers based on optical tweezer arrays.

arXiv:2508.04109•Physical Review A•Sep 24, 2025•3 citations

Lifetime of the 7s6d D12 atomic state of radium

William L. Trimble, Ibrahim Sulai, Irshad Ahmad +8 more

The lifetime of the $7s6d$ ${^{1}D}_{2}$ state of atomic radium is determined to be $385(45)\text{ }\ensuremath{\mu}\text{s}$ using cold $^{226}\text{R}\text{a}$ atoms prepared in a magneto-optical trap. The ${^{1}D}_{2}$ state is populated from the decay of the ${^{1}P}_{1}$ state which is excited by a pulse of 483 nm light. The decay of the ${^{1}D}_{2}$ state is observed by detecting delayed fluorescence at 714 nm from the last step in the decay sequence ${^{1}P}_{1}\text{\ensuremath{-}}{^{1}D}_{2}\text{\ensuremath{-}}{^{3}P}_{1}\text{\ensuremath{-}}{^{1}S}_{0}$. The measured lifetime is compared to a number of theoretical calculations. An improved value of the $7s7p$ ${^{1}P}_{1}$ level of $20\text{ }715.598(6)\text{ }{\text{cm}}^{\ensuremath{-}1}$ is obtained.

Physical Review A•Nov 10, 2009•13 citations
Magneto-optically trapped atoms enable the determination of lifetimes of metastable states and higher lying excited states like the 5d23F25{d}^{2}{\phantom{\rule{0.28em}{0ex}}}^{3}{F}_{2}5d23F2​ state in barium. The state is efficiently populated by driving strong transitions from metastable states within the cooling cycle of the barium magneto-optical trap (MOT). The lifetime is inferred from the increase of MOT fluorescence after the transfer of up to 3030%30 of the trapped atoms to this state. The radiative decay of the 5d23F25{d}^{2}{\phantom{\rule{0.28em}{0ex}}}^{3}{F}_{2}5d23F2​ state cascades to the cooling cycle of the MOT with a probability of 96.0(7)96.0(7)%96.0(7) corresponding to a trap loss of 4.0(7)4.0(7)%4.0(7) and its lifetime is determined to 160(10)\ensuremathμs160(10)\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}160(10)\ensuremathμs. This is in good agreement with the theoretically calculated lifetime of 190\ensuremathμs190\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}190\ensuremathμs [V. A. Dzuba and V. V. Flambaum, J. Phys. B 40, 227 (2007)]. The determined loss of 4.0(7)4.0(7)%4.0(7) from the cooling cycle is compared with the theoretically calculated branching ratios. This measurement extends the efficacy of trapped atoms to measure lifetimes of higher, long-lived states and validate the atomic structure calculations of heavy multielectron systems.
Laser cooling and trapping of the heavy alkaline-earth-metal element barium has been achieved based on the strong $6{s}^{2}\text{ }{^{1}S}_{0}\text{\ensuremath{-}}6s6p\text{ }{^{1}P}_{1}$ transition. The excited state decays to a large fraction into metastable DDD states. Two schemes were implemented where three additional laser-driven transitions provide closed cooling cycles. This results in a fraction of 50(20)% of the trapped atoms in one of the metastable states. A total efficiency of $0.4(1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}2}$ for slowing a thermal atomic beam and capturing atoms into a magneto-optical trap was obtained. Trap lifetimes of more than 1.5 s were observed. They are shortened at high laser intensities by three photon photoionization losses. The developed scheme can be transferred to other systems with large leakage from the cooling transition, such as Ra which is interesting for sensitive fundamental symmetry research.
Laser cooling and trapping of heavy alkaline-earth element barium have been demonstrated for the first time ever. For any possible cycling transition in barium that could provide strong cooling forces, the excited state has a very large branching probability to metastable states. Additional lasers are thus needed to bring the atoms back in to the cooling cycle. In this work barium atoms were efficiently collected in a magneto-optical trap (MOT) by large optical forces from the strong 6s2 1S0 – 6s6p 1P1 transition. Trapping of barium has been achieved using up to seven lasers simultaneously. The properties of the barium MOT were characterized. The efficiency of capturing an atom from a thermal atomic beam into the MOT is 0.4(1) %. The developed scheme is very efficient for collecting atoms. Loss rate mechanisms from the trap were studied by observing the decay of the trap population. Typical lifetimes of the MOT cloud are on the order of one second and are limited mainly due to insufficient repumping of metastable states. The range of velocities from which barium atoms can be captured into the MOT is about 30 m/s. Different laser transitions were employed for repumping barium atoms from the 6s5d 3D1 and the 6s5d 3D2 states. They lead to similar trap populations and lifetimes. The temperature of the cold atomic barium cloud was determined to about 5 mK. Atomic properties of the 5d2 3F2 state were studied with trapped atoms, in particular it's lifetime was determined as 160(10) s. This work has shown a possible scheme to trap atoms with a leaky cooling cycle. Since atoms with such properties are the majority of the elements in the periodic table, the number of optically trapable elements can be significantly enlarged. Of particular high interest is radium, which is chemical homologue to barium. The interest in radium stems from it's high sensitivity to possible nuclear and electron permanent electric dipole moments (EDM's). An EDM violates parity as well as time reversal and is therefore of fundamental importance. Searches for such EDM's are among the main research goals of the recently commissioned TRImP facility at KVI.
We demonstrate an accurate method for measuring the lifetime of long-lived metastable magnetic states using a magneto-optical trap (MOT). Through optical pumping, the metastable (3s3p) 3P1(3s3p)\text{ }{^{3}P}_{1}(3s3p) 3P1​ level is populated in a standard MOT. During the optical pumping process, a fraction of the population is captured in the magnetic quadrupole field of the MOT. When the metastable atoms decay to the (3s2) 1S0(3{s}^{2})\text{ }{^{1}S}_{0}(3s2) 1S0​ ground state they are recaptured into the MOT. In this system no alternative cascading transition is possible. The lifetime of the metastable level is measured directly as an exponential load time of the MOT. We have experimentally tested our method by measuring the lifetime of the (3s3p) 3P1(3s3p)\text{ }{^{3}P}_{1}(3s3p) 3P1​ of 24Mg^{24}\text{M}\text{g}24Mg. This lifetime has been measured numerous times previously, but with quite different results. Using our method we find the (3s3p) 3P1(3s3p)\text{ }{^{3}P}_{1}(3s3p) 3P1​ lifetime to be $(4.4\ifmmode\pm\else\textpm\fi{}0.2)\text{ }\text{ms}$. Theoretical values point toward a lower value for the lifetime.
We realize a magneto-optical trap (MOT) of titanium (Ti) atoms, performing laser cooling on the 498 nm transition between the long-lived 3 d 3 ( F 4 ) 4 s a 5 F 5 metastable state and the 3 d 3 ( F 4 ) 4 p y 5 G 6 o excited state. Without the addition of any repumping light, we observe MOTs of the three stable, I = 0 bosonic isotopes, Ti 46 , Ti 48 , and Ti 50 . Up to 8.30 ( 26 ) × 10 5 Ti 48 atoms are trapped at a maximum density of 1.3 ( 4 ) × 10 11 cm − 3 and at a temperature of 90 ( 15 ) µ K . By measuring the decay of the MOT, we constrain the leakage branching ratio of the cooling transition ( ≤ 2.5 × 10 − 6 ) and the two-body loss coefficient ( ≤ 2 × 10 − 10 cm 3 s − 1 ). Our approach to laser cooling Ti can be applied to other transition metals, enabling a significant expansion of the elements that can be laser cooled.
We explore the efficacy of optical pumping on the $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}\text{\ensuremath{-}}5s8p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}$ (448nm)(448\phantom{\rule{0.16em}{0ex}}\mathrm{nm})(448nm) transition in a magneto-optical trap (MOT) of Sr atoms. The number of trapped atoms is enhanced by a factor of 12.0(6)12.0(6)12.0(6) relative to the case without repumping light, which is six times as large as that obtained using the pumping transition $5s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}\text{\ensuremath{-}}5s6p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}$ (717nm)(717\phantom{\rule{0.16em}{0ex}}\mathrm{nm})(717nm). This enhancement is limited by decay pathways that bypass the 5s4d1D25s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}5s4d1D2​ state, namely $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{1}\ensuremath{\rightarrow}5s5p\phantom{\rule{0.16em}{0ex}}^{3}P_{0}$ and $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{2}\ensuremath{\rightarrow}5s5p\phantom{\rule{0.16em}{0ex}}^{3}P_{2}$, which account for 8% of the total loss of the trapped atoms. We determine the decay rates for the $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{1}$ and $5s5p\phantom{\rule{0.16em}{0ex}}^{1}P_{1}\ensuremath{\rightarrow}5s4d\phantom{\rule{0.16em}{0ex}}^{3}D_{2}$ transitions to be $66(6)\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$ and $2.4(2)\ifmmode\times\else\texttimes\fi{}{10}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$, respectively. Furthermore, we experimentally demonstrate, when the trap beam diameter is small, escape of atoms in the 5s4d1D25s4d\phantom{\rule{0.16em}{0ex}}^{1}D_{2}5s4d1D2​ state, which has a relatively long lifetime of $400\phantom{\rule{0.16em}{0ex}}\textmu{}\mathrm{s}$, becomes a dominant loss mechanism, and that the 448nm448\phantom{\rule{0.16em}{0ex}}\mathrm{nm}448nm pumping light effectively suppresses this escape. Our findings will contribute to improved laser cooling and fluorescence imaging in cold strontium atom platforms, such as quantum computers based on optical tweezer arrays.
The lifetime of the 7s6d7s6d7s6d 1D2{^{1}D}_{2}1D2​ state of atomic radium is determined to be $385(45)\text{ }\ensuremath{\mu}\text{s}$ using cold 226Ra^{226}\text{R}\text{a}226Ra atoms prepared in a magneto-optical trap. The 1D2{^{1}D}_{2}1D2​ state is populated from the decay of the 1P1{^{1}P}_{1}1P1​ state which is excited by a pulse of 483 nm light. The decay of the 1D2{^{1}D}_{2}1D2​ state is observed by detecting delayed fluorescence at 714 nm from the last step in the decay sequence ${^{1}P}_{1}\text{\ensuremath{-}}{^{1}D}_{2}\text{\ensuremath{-}}{^{3}P}_{1}\text{\ensuremath{-}}{^{1}S}_{0}$. The measured lifetime is compared to a number of theoretical calculations. An improved value of the 7s7p7s7p7s7p 1P1{^{1}P}_{1}1P1​ level of $20\text{ }715.598(6)\text{ }{\text{cm}}^{\ensuremath{-}1}$ is obtained.