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:physics/0310074 · Physical Review Letters

Lifetime Measurement of the P 2 3 Metastable State of Strontium Atoms

Masami Yasuda, Hidetoshi Katori

Published Apr 15, 2004• 74 citations
arXivHTMLPDF

Abstract

We have measured the lifetime of the 5s5p 3P2 metastable state of strontium atoms by magneto-optically trapping the decayed atoms to the ground state, which allowed sensitive detection of the rare decay events. We found that the blackbody radiation-induced decay was the dominant decay channel for the state at T=300 K. The lifetime was determined to be 520(+310)(-140) s in the limit of zero temperature, arguably the longest lifetime ever determined in a laboratory environment.

DOI
10.1103/physrevlett.92.153004

Related papers

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

Subhadeep De, Umakanth Dammalapati, Lorenz Willmann

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.

arXiv:1502.07855•Physical Review A•Mar 26, 2015•1 citation

Magnetic trapping of metastable 3P2 atomic strontium

Sarah Nagel, Clayton E. Simien, S. Laha +3 more

We report the magnetic trapping of metastable ${}^{3}{P}_{2}$ atomic strontium. Atoms are cooled in a magneto-optical trap (MOT) operating on the dipole-allowed ${}^{1}{S}_{0}{\ensuremath{-}}^{1}{P}_{1}$ transition at 461 nm. Decay via ${}^{1}{\stackrel{\ensuremath{\rightarrow}}{{P}_{1}}}^{1}{\stackrel{\ensuremath{\rightarrow}}{{D}_{2}}}^{3}{P}_{2}$ continuously loads a magnetic trap formed by the quadrupole magnetic field of the MOT. Over ${10}^{8}$ atoms at a density of $8\ifmmode\times\else\texttimes\fi{}{10}^{9}{\mathrm{cm}}^{\ensuremath{-}3}$ and temperature of 1 mK are trapped. The atom temperature is significantly lower than what would be expected from the kinetic and potential energies of atoms as they are transferred from the MOT. This suggests the occurrence of thermalization and evaporative cooling in the magnetic trap.

arXiv:physics/0212024•Physical Review A•Jan 13, 2003•96 citations

Lifetime measurement of the 1 s5 metastable state of argon and krypton with a magneto-optical trap

Hidetoshi Katori, Fujio Shimizu

The natural decay rates of the 1${\mathit{s}}_{5}$[${\mathit{np}}^{5}$(n+1)s${,}^{3}$${\mathit{P}}_{2}$] metastable state of argon and krypton are experimentally determined using a magneto-optical trap. The method to determine the lifetime of a metastable state from a fluorescence decay measurement is described. The obtained lifetimes are ${38}_{\mathrm{\ensuremath{-}}5}^{+8}$ s for argon and ${39}_{\mathrm{\ensuremath{-}}4}^{+5}$ s for krypton.

Physical Review Letters•Jun 7, 1993•79 citations

Direct measurement of the P 0 3 clock state natural lifetime in Sr 87

Jonathan Dolde, D. Ganapathy, Xin Zheng +3 more

Optical lattice clocks based on the narrow ( 5 s 2 ) S 0 1 − ( 5 s 5 p ) P 0 3 transition in neutral strontium (Sr) are among the most precise and accurate measurement devices in existence. Although this transition is completely forbidden by selection rules, state mixing from the hyperfine interaction in Sr 87 provides a weakly allowed transition that can be coherently driven with practical clock laser intensities. While the coherent interrogation times of optical clocks are typically set by the linewidth of the probe laser, this limitation can be overcome in synchronous differential comparisons between ensembles. In such measurements the natural lifetime of the S 0 1 – P 0 3 clock transition becomes the fundamental limiting factor to the duration of a single run of the experiment. However, a direct measurement of the decay rate of the clock excited state is quite challenging due to the competing effects of other loss channels such as Raman scattering, inelastic collisions, and atom loss due to background gas. In this work, we monitor the decay of Sr atoms trapped in an optical lattice and initialized in the P 0 3 state. By making measurements of high and low density ensembles of both Sr 87 and Sr 88 across varying lattice trap depths, we isolate radiative decay, which accounts for a significant fraction of the observed decays at low depths. We obtain a natural radiative decay lifetime of 167 − 40 + 79 s for the P 0 3 clock state in Sr 87 , a value that is consistent with previously reported measurements and theoretical predictions. We also introduce an additional measurement scheme that involves repeated measurements of the ground-state population within a single experimental sequence, validating our model and the consistency of the measured rates. We expect that the techniques introduced in this work are applicable to lifetime measurements of long-lived metastable states in other atoms and ions used for clocks and quantum computing. The results presented in this work inform performance estimates of proposed gravitational wave detectors and long-baseline atom interferometers making use of Sr 87 .

arXiv:2505.06440•Physical Review A•Jul 29, 2025•4 citations

Direct measurement of the metastable 3P2 decay rate in krypton

J. Lefers, N. Miller, David S. N. Rupke +2 more

We use a magneto-optical trap to isolate ${}^{84}\mathrm{Kr}$ atoms in the metastable ${}^{3}{P}_{2}$ state and then measure the rate of 125.0-nm fluorescence due to spontaneous magnetic quadrupole $(M2)$ decay. We normalize the overall fluorescence rate from the sample using a ``quenching'' process in which laser excitation provides a path for prompt decay to the ground state, with each atom emitting one 123.6-nm photon. A single, solar-blind photomultiplier tube is used to detect both the $M2$ and the quench-induced photons, so that only small corrections relating to spectral response are necessary. We find a spontaneous decay rate of $\ensuremath{\Gamma}=0.0354(22){\mathrm{s}}^{\ensuremath{-}1},$ which translates into a lifetime of 28.3(1.8) s. This result is discussed in the context of previous measurements and calculations of ${}^{3}{P}_{2}$ lifetimes in the rare gases.

Physical Review A•Jul 30, 2002•18 citations

Lifetime of the metastable 6s′ [1/2]_0 clock state in xenon

M. Walhout, Uwe Sterr, A. Witte +1 more

To investigate the potential of a proposed optical frequency standard, we have measured the lifetime of the metastable 6s' [(1/2)](0) state in xenon. Magneto-optically trapped xenon atoms were prepared in the 6s' [(1/2)](0) state, and the time dependence of the vacuum-ultraviolet decay signature was analyzed. The total decay rate of 75(3) s(-1) is the sum of a 7.8(38)-s(-1) spontaneous emission rate (1-sigma uncertainties) and a much larger deexcitation rate that is due to a transition driven by room-temperature blackbody radiation.

Optics Letters•May 15, 1995•24 citations
We have measured the lifetime of the 5s5p 3P2 metastable state of strontium atoms by magneto-optically trapping the decayed atoms to the ground state, which allowed sensitive detection of the rare decay events. We found that the blackbody radiation-induced decay was the dominant decay channel for the state at T=300 K. The lifetime was determined to be 520(+310)(-140) s in the limit of zero temperature, arguably the longest lifetime ever determined in a laboratory environment.
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 $160(10)\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{s}$. 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)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.
We report the magnetic trapping of metastable 3P2{}^{3}{P}_{2}3P2​ atomic strontium. Atoms are cooled in a magneto-optical trap (MOT) operating on the dipole-allowed ${}^{1}{S}_{0}{\ensuremath{-}}^{1}{P}_{1}$ transition at 461 nm. Decay via ${}^{1}{\stackrel{\ensuremath{\rightarrow}}{{P}_{1}}}^{1}{\stackrel{\ensuremath{\rightarrow}}{{D}_{2}}}^{3}{P}_{2}$ continuously loads a magnetic trap formed by the quadrupole magnetic field of the MOT. Over 108{10}^{8}108 atoms at a density of $8\ifmmode\times\else\texttimes\fi{}{10}^{9}{\mathrm{cm}}^{\ensuremath{-}3}$ and temperature of 1 mK are trapped. The atom temperature is significantly lower than what would be expected from the kinetic and potential energies of atoms as they are transferred from the MOT. This suggests the occurrence of thermalization and evaporative cooling in the magnetic trap.
The natural decay rates of the 1s5{\mathit{s}}_{5}s5​[np5{\mathit{np}}^{5}np5(n+1)s,3{,}^{3},3P2{\mathit{P}}_{2}P2​] metastable state of argon and krypton are experimentally determined using a magneto-optical trap. The method to determine the lifetime of a metastable state from a fluorescence decay measurement is described. The obtained lifetimes are ${38}_{\mathrm{\ensuremath{-}}5}^{+8}$ s for argon and ${39}_{\mathrm{\ensuremath{-}}4}^{+5}$ s for krypton.
Optical lattice clocks based on the narrow ( 5 s 2 ) S 0 1 − ( 5 s 5 p ) P 0 3 transition in neutral strontium (Sr) are among the most precise and accurate measurement devices in existence. Although this transition is completely forbidden by selection rules, state mixing from the hyperfine interaction in Sr 87 provides a weakly allowed transition that can be coherently driven with practical clock laser intensities. While the coherent interrogation times of optical clocks are typically set by the linewidth of the probe laser, this limitation can be overcome in synchronous differential comparisons between ensembles. In such measurements the natural lifetime of the S 0 1 – P 0 3 clock transition becomes the fundamental limiting factor to the duration of a single run of the experiment. However, a direct measurement of the decay rate of the clock excited state is quite challenging due to the competing effects of other loss channels such as Raman scattering, inelastic collisions, and atom loss due to background gas. In this work, we monitor the decay of Sr atoms trapped in an optical lattice and initialized in the P 0 3 state. By making measurements of high and low density ensembles of both Sr 87 and Sr 88 across varying lattice trap depths, we isolate radiative decay, which accounts for a significant fraction of the observed decays at low depths. We obtain a natural radiative decay lifetime of 167 − 40 + 79 s for the P 0 3 clock state in Sr 87 , a value that is consistent with previously reported measurements and theoretical predictions. We also introduce an additional measurement scheme that involves repeated measurements of the ground-state population within a single experimental sequence, validating our model and the consistency of the measured rates. We expect that the techniques introduced in this work are applicable to lifetime measurements of long-lived metastable states in other atoms and ions used for clocks and quantum computing. The results presented in this work inform performance estimates of proposed gravitational wave detectors and long-baseline atom interferometers making use of Sr 87 .
We use a magneto-optical trap to isolate 84Kr{}^{84}\mathrm{Kr}84Kr atoms in the metastable 3P2{}^{3}{P}_{2}3P2​ state and then measure the rate of 125.0-nm fluorescence due to spontaneous magnetic quadrupole (M2)(M2)(M2) decay. We normalize the overall fluorescence rate from the sample using a ``quenching'' process in which laser excitation provides a path for prompt decay to the ground state, with each atom emitting one 123.6-nm photon. A single, solar-blind photomultiplier tube is used to detect both the M2M2M2 and the quench-induced photons, so that only small corrections relating to spectral response are necessary. We find a spontaneous decay rate of $\ensuremath{\Gamma}=0.0354(22){\mathrm{s}}^{\ensuremath{-}1},$ which translates into a lifetime of 28.3(1.8) s. This result is discussed in the context of previous measurements and calculations of 3P2{}^{3}{P}_{2}3P2​ lifetimes in the rare gases.
To investigate the potential of a proposed optical frequency standard, we have measured the lifetime of the metastable 6s' [(1/2)](0) state in xenon. Magneto-optically trapped xenon atoms were prepared in the 6s' [(1/2)](0) state, and the time dependence of the vacuum-ultraviolet decay signature was analyzed. The total decay rate of 75(3) s(-1) is the sum of a 7.8(38)-s(-1) spontaneous emission rate (1-sigma uncertainties) and a much larger deexcitation rate that is due to a transition driven by room-temperature blackbody radiation.