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

Optics Letters

Inversion of the resonance line of Sr^+ produced by optically pumping Sr atoms

William R. Green, R. W. Falcone

Published May 1, 1978• 7 citations
Publisher

Abstract

We report inversion and lasing on the optically pumped resonance line of Sr+. A mode-locked frequency-doubled dye laser was tuned to excite the dipole-allowed two-electron transition, 5S(2) (1)S(0)-4d5p (3)P1(0), in Sr vapor. The same laser then ionized the excited atoms, selectively producing ions in the Sr+ 5p (2)p(3/2)(0) excited level. The inversion density with respect to the Sr+ ground level was approximately 10(13) cm(-3).

DOI
10.1364/ol.2.000115

Related papers

Single and double ionization of strontium in the vicinity of four-photon excitation of the 5p2 1S0doubly excited state

Ioannis Liontos, S. Cohen, Agisilaos Bolovinos

We report on the single and double multiphoton ionization of ground state Sr atoms observed in an atomic beam experiment with laser pulses of ∼5 ns duration, maximum intensity ∼4 × 10 11 W cm −2 and within the 710–740 nm wavelength range. The Sr + spectrum consists of two strong lines originating from three-photon resonant four-photon ionization of bound states, a number of weak autoionizing resonances and a broad line due to four-photon excitation of the doubly excited 5p 2 1 S 0 state. The latter, along with a strong, broad and structured spectral feature, is also evident in the wavelength dependence of the doubly charged Sr 2+ ion. A weakly evident but reproducible inflection point ('knee' structure) appears in the intensity dependence of the Sr 2+ yield at the location of the 5p 2 1 S 0 resonance. A complementary fluorescence experiment revealed the accumulation of population in the 5p 1/2 , 3/2 , 6s 1/2 and 5d 3/2 , 5/2 excited Sr + states during the laser pulse. All fluorescence signals depend on laser wavelength in a manner similar to the recorded Sr + spectrum. The population accumulation in the 5p 1/2 , 3/2 ionic states unambiguously proves the absorption of two photons above the first 5s 1/2 atomic threshold while that of the 5d 3/2 , 5/2 and 6s 1/2 ones suggest the absorption of at least two more. Since under our laser pulse duration and intensity the absorption of such a number of photons in an unstructured continuum is highly improbable, it may be concluded that the process is mediated by dense manifolds of near- resonant doubly excited states, their role in the dynamics of laser–atom interaction under our conditions being far more crucial than in studies conducted using intense ultrashort pulses.

Journal of Physics B Atomic Molecular and Optical Physics•Feb 11, 2008•13 citations

Observation of selective excitation in laser-pumped rubidium

Daniel Joseph Bradley, G. M. Gale, P D Smith

The 5P 3/2 level of rubidium has been selectively populated by a narrow-band dye laser tuned to resonance with the 5S 1/2 to 5P 3/2 transition. The upper-state absorption line at lambda 7758 AA (5P 3/2 -5D 5/2 ) has been simultaneously recorded with a second broad-band dye laser continuum.

Journal of Physics B Atomic and Molecular Physics•Jan 1, 1970•21 citations

Production of large numbers of atoms in a selected excited state by laser optical pumping: calcium

Thomas J. Mcilrath, John L. Carlsten

An experiment is described in which large numbers ( approximately 10 16 ) of calcium atoms are placed in the 4s4p 3 P metastable level by optical pumping with a tunable dye laser and then studied spectroscopically. Equations governing the degree of excitation by the laser are derived. Predictions of the theory are shown to be in good agreement with experimental results. In particular, at low optical depths produced by 10 15 ground state atoms cm -2 the dye laser raises approximately 50% of the calcium atoms into the metastable state. At higher optical depths associated with 10 17 ground state atoms cm -2 the number of excited states is limited only by the laser energy and line width. For the dye laser used the largest number of metastables produced was approximately 10 16 . The absorption spectra of the 4s4p 2 P level is seen out to 4s4p 3 P to 4s22d 3 D. The relaxation rate between the excited state fine structure is studied directly with an optically delayed dye laser continuum. Other applications of this technique of producing large numbers of excited states are briefly discussed.

Journal of Physics B Atomic and Molecular Physics•Apr 1, 1973•45 citations

Lasing in barium vapor in a resonant optical field

Iosif S. Zeilikovich, S. A. Pulkin, Л. С. Гайда

Lasing was achieved in barium vapor near an absorption line at the λ = 553.5 nm wavelength corresponding to the 61S0–61P1 resonance transition. Barium vapor produced in an arc discharge was placed in the resonator of a dye laser having a stimulated emission spectrum of ~ 5 pm half-width. In the presence of additional weak broad-band radiation, the lasing spectrum consisted of two components symmetric relative to the center of the absorption line. This lasing was due to stimulated Raman scattering by a population grating and was most efficient in regions where the difference between the frequencies of the strong and weak fields coincided with the Rabi frequency. A quantitative comparison was made between theory and experiment on amplification without population inversion in a two-level system. Holographic interference spectroscopy was used to study experimentally the behavior of the susceptibility (the absorption coefficient and the refractive index) under conditions of resonant interaction. Good agreement was obtained between the behavior of the dispersion of the refractive index and the theoretical dependence. The highest gains were kv ≈ 10 cm −1 when the barium atomic concentration was N ≈ 5 × 1016 cm −3.

Soviet Journal of Quantum Electronics•Feb 28, 1988•0 citations

Multiphoton single and double ionisation of strontium in the range 532-541 nm

Pierre Camus, Μιχάλης Κομπίτσας, S. Cohen +4 more

By focusing an excimer pumped dye laser on an atomic beam, the authors have observed multiphoton multiple ionisation of the neutral strontium atom in the tuned wavelength range 532-41 nm. Sr + and Sr ++ yields were measured with a time of flight spectrometer. At least three photons are required to produce Sr + and eight photons to produce Sr ++ . As a function of the wavelength, the Sr + yield exhibits resonances which correspond to two-photon excitation of bound states (5s 2 -5p 2 1 D 2 and 5s 2 -5p 2 1 S 0 ) and three-photon excitation of autoionising states 4d5f J=1 and J=3 of the neutral atom. The Sr ++ yield exhibits four broad smooth resonances that they interpret, from known spectroscopic data, as two-photon (5p 1/2 -4f), three-photon (5s-6p 1/2, 3/2 ) and four-photon (5s-7d) resonances in the singly charged ion. The latter transitions start from a singly charged ion in the 5s or 5p 1/2 state reached after three- or four-photon ionisation of the neutral ground state. The variation of the Sr ++ pattern as a function of the dye laser beam intensity shows that resonances are shifted and broadened when the intensity is increased. These features have been interpreted by a perturbative treatment of Sr + ionisation based on the use of an effective Hamiltonian which takes into account higher-order terms involved in the calculation of resonance effects. Calculated multiphoton ionisation probabilities are in good agreement with experimental data.

Journal of Physics B Atomic Molecular and Optical Physics•Feb 14, 1989•26 citations

Lasing on the D2 line of sodium in a helium atmosphere due to optical pumping on the D1 line (up-conversion)

A. A. Apolonsky, Sergey A. Babin, Sergey I. Kablukov +3 more

A method is proposed to produce population inversion on transitions involving the ground state of atoms. The method is realized experimentally with sodium atoms. Lasing at the frequency corresponding to the sodium ${D}_{2}$ line is achieved in the presence of pump radiation resonant to the ${D}_{1}$ line with helium as a buffer gas.

arXiv:physics/9906036•Physical Review A•Feb 15, 2000•8 citations
We report inversion and lasing on the optically pumped resonance line of Sr+. A mode-locked frequency-doubled dye laser was tuned to excite the dipole-allowed two-electron transition, 5S(2) (1)S(0)-4d5p (3)P1(0), in Sr vapor. The same laser then ionized the excited atoms, selectively producing ions in the Sr+ 5p (2)p(3/2)(0) excited level. The inversion density with respect to the Sr+ ground level was approximately 10(13) cm(-3).
We report on the single and double multiphoton ionization of ground state Sr atoms observed in an atomic beam experiment with laser pulses of ∼5 ns duration, maximum intensity ∼4 × 10 11 W cm −2 and within the 710–740 nm wavelength range. The Sr + spectrum consists of two strong lines originating from three-photon resonant four-photon ionization of bound states, a number of weak autoionizing resonances and a broad line due to four-photon excitation of the doubly excited 5p 2 1 S 0 state. The latter, along with a strong, broad and structured spectral feature, is also evident in the wavelength dependence of the doubly charged Sr 2+ ion. A weakly evident but reproducible inflection point ('knee' structure) appears in the intensity dependence of the Sr 2+ yield at the location of the 5p 2 1 S 0 resonance. A complementary fluorescence experiment revealed the accumulation of population in the 5p 1/2 , 3/2 , 6s 1/2 and 5d 3/2 , 5/2 excited Sr + states during the laser pulse. All fluorescence signals depend on laser wavelength in a manner similar to the recorded Sr + spectrum. The population accumulation in the 5p 1/2 , 3/2 ionic states unambiguously proves the absorption of two photons above the first 5s 1/2 atomic threshold while that of the 5d 3/2 , 5/2 and 6s 1/2 ones suggest the absorption of at least two more. Since under our laser pulse duration and intensity the absorption of such a number of photons in an unstructured continuum is highly improbable, it may be concluded that the process is mediated by dense manifolds of near- resonant doubly excited states, their role in the dynamics of laser–atom interaction under our conditions being far more crucial than in studies conducted using intense ultrashort pulses.
An experiment is described in which large numbers ( approximately 10 16 ) of calcium atoms are placed in the 4s4p 3 P metastable level by optical pumping with a tunable dye laser and then studied spectroscopically. Equations governing the degree of excitation by the laser are derived. Predictions of the theory are shown to be in good agreement with experimental results. In particular, at low optical depths produced by 10 15 ground state atoms cm -2 the dye laser raises approximately 50% of the calcium atoms into the metastable state. At higher optical depths associated with 10 17 ground state atoms cm -2 the number of excited states is limited only by the laser energy and line width. For the dye laser used the largest number of metastables produced was approximately 10 16 . The absorption spectra of the 4s4p 2 P level is seen out to 4s4p 3 P to 4s22d 3 D. The relaxation rate between the excited state fine structure is studied directly with an optically delayed dye laser continuum. Other applications of this technique of producing large numbers of excited states are briefly discussed.
Lasing was achieved in barium vapor near an absorption line at the λ = 553.5 nm wavelength corresponding to the 61S0–61P1 resonance transition. Barium vapor produced in an arc discharge was placed in the resonator of a dye laser having a stimulated emission spectrum of ~ 5 pm half-width. In the presence of additional weak broad-band radiation, the lasing spectrum consisted of two components symmetric relative to the center of the absorption line. This lasing was due to stimulated Raman scattering by a population grating and was most efficient in regions where the difference between the frequencies of the strong and weak fields coincided with the Rabi frequency. A quantitative comparison was made between theory and experiment on amplification without population inversion in a two-level system. Holographic interference spectroscopy was used to study experimentally the behavior of the susceptibility (the absorption coefficient and the refractive index) under conditions of resonant interaction. Good agreement was obtained between the behavior of the dispersion of the refractive index and the theoretical dependence. The highest gains were kv ≈ 10 cm −1 when the barium atomic concentration was N ≈ 5 × 1016 cm −3.
By focusing an excimer pumped dye laser on an atomic beam, the authors have observed multiphoton multiple ionisation of the neutral strontium atom in the tuned wavelength range 532-41 nm. Sr + and Sr ++ yields were measured with a time of flight spectrometer. At least three photons are required to produce Sr + and eight photons to produce Sr ++ . As a function of the wavelength, the Sr + yield exhibits resonances which correspond to two-photon excitation of bound states (5s 2 -5p 2 1 D 2 and 5s 2 -5p 2 1 S 0 ) and three-photon excitation of autoionising states 4d5f J=1 and J=3 of the neutral atom. The Sr ++ yield exhibits four broad smooth resonances that they interpret, from known spectroscopic data, as two-photon (5p 1/2 -4f), three-photon (5s-6p 1/2, 3/2 ) and four-photon (5s-7d) resonances in the singly charged ion. The latter transitions start from a singly charged ion in the 5s or 5p 1/2 state reached after three- or four-photon ionisation of the neutral ground state. The variation of the Sr ++ pattern as a function of the dye laser beam intensity shows that resonances are shifted and broadened when the intensity is increased. These features have been interpreted by a perturbative treatment of Sr + ionisation based on the use of an effective Hamiltonian which takes into account higher-order terms involved in the calculation of resonance effects. Calculated multiphoton ionisation probabilities are in good agreement with experimental data.
A method is proposed to produce population inversion on transitions involving the ground state of atoms. The method is realized experimentally with sodium atoms. Lasing at the frequency corresponding to the sodium D2{D}_{2}D2​ line is achieved in the presence of pump radiation resonant to the D1{D}_{1}D1​ line with helium as a buffer gas.