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

Physical Review Letters

Crossed-Beam Determination of Na—Rare-Gas Fine-Structure-State—Changing Cross Sections

William D. Phillips, Charles L. Glaser, Daniel Kleppner

Published May 2, 1977• 35 citations
Publisher

Abstract

We report first measurements of the velocity dependence of an alkali-rare-gas fine-structure-state-changing collision with adequate range and resolution to reveal a peak in the cross section. The method uses crossed atomic beams and selective laser excitation. Results are presented for Na colliding with Ne, Ar, and Kr. The results for Na-Ar are in good agreement with theory, while those for Na-Ne and Na-Kr are in serious disagreement.

DOI
10.1103/physrevlett.38.1018

Related papers

Angular Scattering Distribution By Doppler Spectroscopy: Na(3P12)+Ar→Na(3P32)+Ar

William D. Phillips, John A. Serri, Douglas J. Ely +3 more

We have developed a new method for determining state-resolved differential cross sections in inelastic collisions. A single-frequency laser provides level-specific detection of scattered atoms, while the Doppler shift of the same laser provides a completely non-mechanical angular selectivity in the detection. We have used this technique to make the first measurement of an alkali fine-structure transfer cross section in which both the scattering angle and final state are determined.

Physical Review Letters•Oct 2, 1978•46 citations

Experimental fine-structure branching ratios for Na–rare-gas optical collisions

Mark D. Havey, F. T. Delahanty, Linda L. Vahala +1 more

Experimental ratios for branching into the fine-structure levels of the Na 3p multiplet, as a consequence of an optical collision with He, Ne, Ar, Kr, or Xe, are reported. The process studied is Na(3s $^{2}S_{1/2}$)+scrR+nh\ensuremath{\nu}\ensuremath{\rightarrow} Na(3p $^{2}P_{j}$)+scrR+(n-1)h\ensuremath{\nu} , where scrR represents a rare-gas atom and where the laser frequency \ensuremath{\nu} is tuned in the wings of the Na resonance transitions. The branching ratios are defined as I(D1)/I(D2) where I(D1) and I(D2) are measured intensities of the atomic Na D1 and D2 lines. The ratios are determined for detunings ranging from about 650 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in the blue wing to 170 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in the red wing of the Na 3p multiplet. The branching is found to be strongly detuning dependent in the vicinity of the NaAr, NaKr, and NaXe near-red-wing satellites. The blue-wing branching ratios show a detuning-dependent approach to a recoil, or sudden statistical, limit of 0.5, irrespective of the rare gas. Fine-structure changing cross sections have also been measured for resonant excitation of the Na 3p $^{2}P_{j}$ state; the results are consistent with cross sections obtained from wing excitation.

Physical Review A•Oct 1, 1986•21 citations

Theory of fine structure transitions in excited rubidium atoms colliding with rare gas atoms

Martin B. Hidalgo, S. Geltman

A theoretical model is presented for the interaction between an alkali atom in the first excited 2 P state and a ground state rare gas atom, which is effective in causing transitions among the alkali fine structure states. The main difference from previously used models is a more detailed treatment of short range effects including deviations from straight line paths in the semiclassical treatment. An application to the case of Rb interacting with He, Ne, Ar, and Kr gives results for the depolarization and inelastic cross sections which are in reasonable accord with experiment.

Journal of Physics B Atomic and Molecular Physics•Feb 1, 1972•10 citations

Collision-Induced Mixing in the First Excited States of Sodium and Potassium

J. A. Jordan, P. A. Franken

The cross sections for the collision-induced transfer of excitation from the $^{2}P_{\frac{3}{2}}$ level to the $^{2}P_{\frac{1}{2}}$ level of the first excited states of the alkali atoms have been measured for several alkali-noble gas systems. The cross sections were determined with a conventional resonance fluorescence technique in which the radiation from a spectral source was absorbed and re-emitted by an alkali vapor at low pressure (\ensuremath{\sim}${10}^{\ensuremath{-}6}$ Torr), and the scattered light analyzed with a scanning spectrometer. Provision was made for the introduction of various noble gases at controlled pressures into the alkali vapor. The determined cross sections are (in units of ${10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$): Na-He, 41.1\ifmmode\pm\else\textpm\fi{}2.9; Na-Ne, 36.1\ifmmode\pm\else\textpm\fi{}2.5; Na-Ar, 64.6\ifmmode\pm\else\textpm\fi{}5.2; Na-Kr, 68.2\ifmmode\pm\else\textpm\fi{}5.5; Na-Xe, 61.8\ifmmode\pm\else\textpm\fi{}4.9; K-He, 52.8\ifmmode\pm\else\textpm\fi{}5.8; K-Ne, 14.0\ifmmode\pm\else\textpm\fi{}1.2; K-Ar, 34.0\ifmmode\pm\else\textpm\fi{}3.1. The quoted errors are estimated 70% confidence intervals. The measurements are compared with other experimental results and with various estimated cross sections.

Physical Review•Feb 4, 1966•39 citations

Experimental determination of Na–noble-gas velocity-changing and fine-structure-changing collision kernels

Jos E. M. Haverkort, J. P. Woerdman, P. R. Berman

We report on an experimental investigation of the collision kernels governing the effects of velocity-changing collisions, fine-structure-changing collisions, and their interplay, for Na--noble-gas pairs. The velocity distributions in the two Na excited-state fine-structure levels and in the Na ground-state hyperfine levels have been measured in the presence of a pump laser which produces velocity-selective excitation. For interpretation of these experiments we use a rate-equation model developed in the context of light-induced drift: the velocity-changing collisions are accounted for by a composite Keilson-Storer kernel describing large-angle and small-angle collisions and the fine-structure-changing collisions are treated in the sudden limit. The model is valid for arbitrarily high pump laser intensities and uses only a single adjustable parameter characterizing the small-angle scattering. It is found that the theory describes the experimental velocity distributions in all four Na levels over a wide range of experimental parameters for each Na--noble-gas pair. The relevance of the collision kernels deduced in the present work is discussed in the context of light-induced drift.

Physical Review A•Dec 1, 1987•26 citations

Experimental fine-structure branching ratios for Na-rare gas optical collisions

Mark D. Havey, F. T. Delahanty, Linda L. Vahala +1 more

Experimental ratios for branching into the fine‐structure levels of the Na 3p multiplet, as a consequence of an optical collision with He, Ne, Ar, Kr, or Xe, are reported. The process studied is Na(3s2S1/2) +RG+nhν → Na(3p2 Pj)+RG+(n−1)hν, where RG represents a rare gas atom and where the laser frequency ν is tuned in the wings of the Na resonance transitions. The branching ratios are defined as I(D1)/I(D2) where I(D1) and I(D2) are measured intensities of the atomic Na D1 and D2 lines. The ratios are determined for detunings ranging from about 650 cm−1 blue to 170 cm−1 red of the Na 3p multiplet. The branching is found to be strongly detuning dependent in the vicinity of the NaKr and NaXe near red‐wing satellites. The blue wing branching ratios show a detuning‐dependent approach to a recoil or sudden statistical limit of 0.5, irrespective of the rare gas.

AIP conference proceedings•Jan 1, 1986•0 citations
We report first measurements of the velocity dependence of an alkali-rare-gas fine-structure-state-changing collision with adequate range and resolution to reveal a peak in the cross section. The method uses crossed atomic beams and selective laser excitation. Results are presented for Na colliding with Ne, Ar, and Kr. The results for Na-Ar are in good agreement with theory, while those for Na-Ne and Na-Kr are in serious disagreement.
Experimental ratios for branching into the fine-structure levels of the Na 3p multiplet, as a consequence of an optical collision with He, Ne, Ar, Kr, or Xe, are reported. The process studied is Na(3s 2S1/2^{2}S_{1/2}2S1/2​)+scrR+nh\ensuremath{\nu}\ensuremath{\rightarrow} Na(3p 2Pj^{2}P_{j}2Pj​)+scrR+(n-1)h\ensuremath{\nu} , where scrR represents a rare-gas atom and where the laser frequency \ensuremath{\nu} is tuned in the wings of the Na resonance transitions. The branching ratios are defined as I(D1)/I(D2) where I(D1) and I(D2) are measured intensities of the atomic Na D1 and D2 lines. The ratios are determined for detunings ranging from about 650 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in the blue wing to 170 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in the red wing of the Na 3p multiplet. The branching is found to be strongly detuning dependent in the vicinity of the NaAr, NaKr, and NaXe near-red-wing satellites. The blue-wing branching ratios show a detuning-dependent approach to a recoil, or sudden statistical, limit of 0.5, irrespective of the rare gas. Fine-structure changing cross sections have also been measured for resonant excitation of the Na 3p 2Pj^{2}P_{j}2Pj​ state; the results are consistent with cross sections obtained from wing excitation.
A theoretical model is presented for the interaction between an alkali atom in the first excited 2 P state and a ground state rare gas atom, which is effective in causing transitions among the alkali fine structure states. The main difference from previously used models is a more detailed treatment of short range effects including deviations from straight line paths in the semiclassical treatment. An application to the case of Rb interacting with He, Ne, Ar, and Kr gives results for the depolarization and inelastic cross sections which are in reasonable accord with experiment.
The cross sections for the collision-induced transfer of excitation from the 2P32^{2}P_{\frac{3}{2}}2P23​​ level to the 2P12^{2}P_{\frac{1}{2}}2P21​​ level of the first excited states of the alkali atoms have been measured for several alkali-noble gas systems. The cross sections were determined with a conventional resonance fluorescence technique in which the radiation from a spectral source was absorbed and re-emitted by an alkali vapor at low pressure (\ensuremath{\sim}${10}^{\ensuremath{-}6}$ Torr), and the scattered light analyzed with a scanning spectrometer. Provision was made for the introduction of various noble gases at controlled pressures into the alkali vapor. The determined cross sections are (in units of ${10}^{\ensuremath{-}16}$ cm2{\mathrm{cm}}^{2}cm2): Na-He, 41.1\ifmmode\pm\else\textpm\fi{}2.9; Na-Ne, 36.1\ifmmode\pm\else\textpm\fi{}2.5; Na-Ar, 64.6\ifmmode\pm\else\textpm\fi{}5.2; Na-Kr, 68.2\ifmmode\pm\else\textpm\fi{}5.5; Na-Xe, 61.8\ifmmode\pm\else\textpm\fi{}4.9; K-He, 52.8\ifmmode\pm\else\textpm\fi{}5.8; K-Ne, 14.0\ifmmode\pm\else\textpm\fi{}1.2; K-Ar, 34.0\ifmmode\pm\else\textpm\fi{}3.1. The quoted errors are estimated 70% confidence intervals. The measurements are compared with other experimental results and with various estimated cross sections.
We report on an experimental investigation of the collision kernels governing the effects of velocity-changing collisions, fine-structure-changing collisions, and their interplay, for Na--noble-gas pairs. The velocity distributions in the two Na excited-state fine-structure levels and in the Na ground-state hyperfine levels have been measured in the presence of a pump laser which produces velocity-selective excitation. For interpretation of these experiments we use a rate-equation model developed in the context of light-induced drift: the velocity-changing collisions are accounted for by a composite Keilson-Storer kernel describing large-angle and small-angle collisions and the fine-structure-changing collisions are treated in the sudden limit. The model is valid for arbitrarily high pump laser intensities and uses only a single adjustable parameter characterizing the small-angle scattering. It is found that the theory describes the experimental velocity distributions in all four Na levels over a wide range of experimental parameters for each Na--noble-gas pair. The relevance of the collision kernels deduced in the present work is discussed in the context of light-induced drift.
Experimental ratios for branching into the fine‐structure levels of the Na 3p multiplet, as a consequence of an optical collision with He, Ne, Ar, Kr, or Xe, are reported. The process studied is Na(3s2S1/2) +RG+nhν → Na(3p2 Pj)+RG+(n−1)hν, where RG represents a rare gas atom and where the laser frequency ν is tuned in the wings of the Na resonance transitions. The branching ratios are defined as I(D1)/I(D2) where I(D1) and I(D2) are measured intensities of the atomic Na D1 and D2 lines. The ratios are determined for detunings ranging from about 650 cm−1 blue to 170 cm−1 red of the Na 3p multiplet. The branching is found to be strongly detuning dependent in the vicinity of the NaKr and NaXe near red‐wing satellites. The blue wing branching ratios show a detuning‐dependent approach to a recoil or sudden statistical limit of 0.5, irrespective of the rare gas.