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

Laser cooled rubidium atoms in the 5D5/2 level: Excitation, photoionization and collisions

B C Duncan

Published Oct 1, 2001• 0 citations
OpenAlex

Abstract

A series of experiments is performed on cold 85Rb atoms confined in a magneto-optical trap. A variation of Stimulated Raman adiabatic passage (STIRAP) is used to transfer population from the 5S 1/2 ground state to the 5D5/2 state with an efficiency exceeding 80%. This process relies on moderately intense pulses arriving in the counterintuitive order, i.e., the upper transition (5P → 5D) driven before the lower transition (5S → 5P ). There is reasonable agreement with computer simulations, excepting a marked discrepancy between measured intensities and those used in the simulations. With a large ensemble of 5D atoms available, the 5D photoionization cross section at four different laser wavelengths (1064, 788, 647 and 532 nm) is determined via trap loss measurements. The theoretical calculations agree well with the experimental results (17.7, 10.9, 7.6 and 5.2 Mb, respectively). An experiment to measure the 5S-5D collisional rate constant sets an order-of-magnitude upper bound of 10−10 cm3/s, assuming all atoms are 5S-5D pairs. ^

Related papers

Photoionization and cold collision studies using trapped atoms

P. L. Gould

The authors have used laser cooling and trapping techniques to investigate photoionization and cold collisions. With laser-trapped Rb, they have measured the photoionization cross section from the first excited (5P) level by observing the photoionization-induced loss rate of neutral atoms from the trap. This technique has the advantage that it directly measures the photoionization rate per atom. Knowing the ionizing laser intensity and the excited-state fraction, the measured loss rate gives the absolute cross section. Using this technique, the Rb 5P photoionization cross section at {approximately}400 nm has been determined with an uncertainty of 9%. The authors are currently attempting to extend this method to the 5D level. Using time-ordered pulses of diode-laser light (similar to the STIRAP technique), they have performed very efficient two-photon excitation of trapped Rb atoms to 5D. Finally, they will present results from a recent collaboration which combines measurements form conventional molecular spectroscopy (single photon and double resonance) with photoassociation collisions of ultracold Na atoms to yield a precise ({le}1 ppm) value for the dissociation energy of the X {Sigma}{sub g}{sub +} ground state of the Na{sub 2} molecule.

Bulletin of the American Physical Society•May 1, 1996•0 citations

Coherent excitation of the 5D5/2level of ultra-cold rubidium atoms with short laser pulses

Stepan Snigirev, Artem A. Golovizin, Gulnara A. Vishnyakova +2 more

We demonstrate the use of stimulated Raman adiabatic passage (STIRAP) for population transfer from the ground state to the 5D5/2 level (5 5 5 ) S P D / / / 1 2 3 2 5 2 in laser-cooled 87 Rb atoms and examine the influence of the time delay between laser pulses, pulse height, pulse duration and frequency detuning from resonance on the efficiency of Rb atom excitation to the 5D5/2 level. In our experiments, the pulse duration was varied widely (30 - 200 ns), which allowed us to assess the effect of spontaneous decay on the population of the 5D5/2 level (natural lifetime, 300 ns). We per- formed numerical calculations with allowance for spontaneous decay from the 5P3/2 and 5D5/2 levels and compared the results to experimental data, which allowed the population of the 5D5/2 level to be determined. The maximum population of the 5D5/2 level in the region under excitation was 80 % of the total number of rubidium atoms.

Quantum Electronics•Aug 29, 2012•11 citations

Efficient 5D Excitation of Trapped Rb Atoms with Pulsed Diode- Laser Light*

W. Supetitz, B C Duncan, D.I. Lee +1 more

The authors have demonstrated that appropriately time-ordered pulses of diode-laser light can provide efficient population transfer in a three-level cascade system. Laser-trapped Rb atoms are excited from the 5S ground state to the highly-excited 5D level (via the 5P intermediate level) with nearly 100% efficiency. Diode-lasers at 780 nm (5S{yields}5P) and 776 nm (5P{yields}5D) are pulsed with acousto-optic modulators to provide the excitation. The variation of transfer efficiency with relative delay between the two pulses is in good agreement with theoretical expectations. Optimum excitation occurs for the counterintuitive pulse ordering, i.e., when the upper transition is driven first.

Bulletin of the American Physical Society•May 1, 1996•0 citations

Ionization spectroscopy in cold rubidium atoms

Leszek Krzemień, Kacper Baster, Krzysztof Brzozowski +3 more

We demonstrate photoionization spectroscopy in cold rubidium atoms trapped in a working magneto-optical trap. Three-photon ionization with two-photon resonance proceeds along various channels, with the step-by-step 5S-5P-5D transition and with the two-photon excitation of the 5D or 7S state. The processes are monitored by measuring ion signals which allow sensitive spectroscopy of weak transitions in a cold-atom sample.

Optica Applicata•Jan 1, 2010•0 citations

Laser-Induced Population Changes of 5P and 5D Levels in Rubidium Vapor

Wang Shu-ying

Enhancement and reduction of the fluorescence intensity in Rb atomic vapor are observed. The reduction is due to a depopulation of the 5P - {3/2 } state upon illumination of a Rb vapor cell with light corresponding to the 5P - {3/2 }→5D - {5/2 } transition. Collisional transfer of the 5D - {5/2 } atoms to the 5D - {3/2 } state, followed by radiative decay to the 5P - {1/2 } state, creates an increase in the population of the 5P - {1/2 } state. The increase in the excited state population results in an increase in the fluorescence intensity of the 5P - {1/2 }→5S - {1/2 } transition. The laser-induced population changes are monitored by the decrease or increase of the corresponding fluorescence signals. Using the steady-state rate equations, the rate constants for the stimulated emission(i.e., 5D - {5/2 }→5P - {3/2 }) is 2.0×10 +8s + {-1 }. The cross section for the fine-structure changing collision(i.e., 5D - {5/2 }→5D - {3/2 }) is 6.4×10 + {-14 }cm +2.

Shinjang dashösi ilmiy jurnili•Jan 1, 2005•0 citations

Measurement of the Rb(5D5/2) photoionization cross section using trapped atoms

B. C. Duncan, V. Sánchez-Villicaña, P. L. Gould +1 more

We report on measurements of the cross section for photoionization of Rb atoms in the highly excited ${5D}_{5/2}$ level at wavelengths ranging from 1064 to 532 nm (photoelectron energies of 0.175 to 1.34 eV). We efficiently populate the ${5D}_{5/2}$ level using coherent two-photon excitation of trapped atoms with pulses in the counterintuitive order. The absolute photoionization cross sections are then measured via the increased loss of atoms from the magneto-optical trap when it is illuminated by the photoionizing light. Our results are in good agreement with new calculations based on the valence-electron parametric potential method.

Physical Review A•Mar 15, 2001•37 citations
A series of experiments is performed on cold 85Rb atoms confined in a magneto-optical trap. A variation of Stimulated Raman adiabatic passage (STIRAP) is used to transfer population from the 5S 1/2 ground state to the 5D5/2 state with an efficiency exceeding 80%. This process relies on moderately intense pulses arriving in the counterintuitive order, i.e., the upper transition (5P → 5D) driven before the lower transition (5S → 5P ). There is reasonable agreement with computer simulations, excepting a marked discrepancy between measured intensities and those used in the simulations. With a large ensemble of 5D atoms available, the 5D photoionization cross section at four different laser wavelengths (1064, 788, 647 and 532 nm) is determined via trap loss measurements. The theoretical calculations agree well with the experimental results (17.7, 10.9, 7.6 and 5.2 Mb, respectively). An experiment to measure the 5S-5D collisional rate constant sets an order-of-magnitude upper bound of 10−10 cm3/s, assuming all atoms are 5S-5D pairs. ^
The authors have used laser cooling and trapping techniques to investigate photoionization and cold collisions. With laser-trapped Rb, they have measured the photoionization cross section from the first excited (5P) level by observing the photoionization-induced loss rate of neutral atoms from the trap. This technique has the advantage that it directly measures the photoionization rate per atom. Knowing the ionizing laser intensity and the excited-state fraction, the measured loss rate gives the absolute cross section. Using this technique, the Rb 5P photoionization cross section at {approximately}400 nm has been determined with an uncertainty of 9%. The authors are currently attempting to extend this method to the 5D level. Using time-ordered pulses of diode-laser light (similar to the STIRAP technique), they have performed very efficient two-photon excitation of trapped Rb atoms to 5D. Finally, they will present results from a recent collaboration which combines measurements form conventional molecular spectroscopy (single photon and double resonance) with photoassociation collisions of ultracold Na atoms to yield a precise ({le}1 ppm) value for the dissociation energy of the X {Sigma}{sub g}{sub +} ground state of the Na{sub 2} molecule.
We demonstrate the use of stimulated Raman adiabatic passage (STIRAP) for population transfer from the ground state to the 5D5/2 level (5 5 5 ) S P D / / / 1 2 3 2 5 2 in laser-cooled 87 Rb atoms and examine the influence of the time delay between laser pulses, pulse height, pulse duration and frequency detuning from resonance on the efficiency of Rb atom excitation to the 5D5/2 level. In our experiments, the pulse duration was varied widely (30 - 200 ns), which allowed us to assess the effect of spontaneous decay on the population of the 5D5/2 level (natural lifetime, 300 ns). We per- formed numerical calculations with allowance for spontaneous decay from the 5P3/2 and 5D5/2 levels and compared the results to experimental data, which allowed the population of the 5D5/2 level to be determined. The maximum population of the 5D5/2 level in the region under excitation was 80 % of the total number of rubidium atoms.
The authors have demonstrated that appropriately time-ordered pulses of diode-laser light can provide efficient population transfer in a three-level cascade system. Laser-trapped Rb atoms are excited from the 5S ground state to the highly-excited 5D level (via the 5P intermediate level) with nearly 100% efficiency. Diode-lasers at 780 nm (5S{yields}5P) and 776 nm (5P{yields}5D) are pulsed with acousto-optic modulators to provide the excitation. The variation of transfer efficiency with relative delay between the two pulses is in good agreement with theoretical expectations. Optimum excitation occurs for the counterintuitive pulse ordering, i.e., when the upper transition is driven first.
Enhancement and reduction of the fluorescence intensity in Rb atomic vapor are observed. The reduction is due to a depopulation of the 5P - {3/2 } state upon illumination of a Rb vapor cell with light corresponding to the 5P - {3/2 }→5D - {5/2 } transition. Collisional transfer of the 5D - {5/2 } atoms to the 5D - {3/2 } state, followed by radiative decay to the 5P - {1/2 } state, creates an increase in the population of the 5P - {1/2 } state. The increase in the excited state population results in an increase in the fluorescence intensity of the 5P - {1/2 }→5S - {1/2 } transition. The laser-induced population changes are monitored by the decrease or increase of the corresponding fluorescence signals. Using the steady-state rate equations, the rate constants for the stimulated emission(i.e., 5D - {5/2 }→5P - {3/2 }) is 2.0×10 +8s + {-1 }. The cross section for the fine-structure changing collision(i.e., 5D - {5/2 }→5D - {3/2 }) is 6.4×10 + {-14 }cm +2.
We report on measurements of the cross section for photoionization of Rb atoms in the highly excited 5D5/2{5D}_{5/2}5D5/2​ level at wavelengths ranging from 1064 to 532 nm (photoelectron energies of 0.175 to 1.34 eV). We efficiently populate the 5D5/2{5D}_{5/2}5D5/2​ level using coherent two-photon excitation of trapped atoms with pulses in the counterintuitive order. The absolute photoionization cross sections are then measured via the increased loss of atoms from the magneto-optical trap when it is illuminated by the photoionizing light. Our results are in good agreement with new calculations based on the valence-electron parametric potential method.