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

Journal of Physics B Atomic Molecular and Optical Physics

Light-induced drift of Na in molecular buffer gases

Marc C. de Lignie, J. P. Woerdman

Published Feb 14, 1990• 14 citations
Publisher

Abstract

Conventional light-induced drift is based on purely elastic velocity-changing collisions. The authors discuss qualitatively the potentialities of light-induced drift originating from inelastic velocity-changing collisions, which may occur in a molecular buffer gas. In such collisions a large fraction of the electronic excitation energy of the absorbing particle may be transformed into kinetic energy thus affecting light-induced drift. The authors report experiments on light-induced drift of Na in various molecular buffer gases and compare these with their predictions.

DOI
10.1088/0953-4075/23/3/012

Related papers

Numerical study of light-induced drift of Na in noble gases

Jos E. M. Haverkort, H. G. C. Werij, J. P. Woerdman

We present a model for light-induced drift (LID) in the Na--noble-gas system which should enable direct comparison with experiment. In contrast to previous theories of LID based on a two-level description of the optical absorbers and on a simplified collision treatment, the present model is based on a realistic description of laser-driven Na atoms immersed in a buffer gas. Starting from the generalized Bloch equations, we introduce a rate-equation model for the velocity distributions in the four important Na levels. The velocity-changing and fine-structure-changing collisions are described using composite Keilson-Storer collision kernels in which all adjustable parameters have been eliminated by using available literature data. We apply the model in numerical calculations of LID as a function of all experimentally accessible parameters. It is found that the ground-state hyperfine splitting can have large effects on LID, whereas the excited-state fine-structure splitting has not. The paper establishes criteria for optimum LID effects; when using a single-frequency laser the maximum attainable drift velocity is predicted to be 13.8 m/s. Using a proper set of boundary conditions, we find a pressure dependence of LID qualitatively different from the predictions based on previous work. Finally, the influence of the collision model is investigated. We find that LID is independent of the shape of the collision kernel, indicating that a strong-collision model is always valid.

Physical Review A•Oct 1, 1988•25 citations

Effect of Light-Induced Drift in Confined Semiconductors Heterostructures,

Mark I. Stockman, Lakshmi N. Pandey, Thomas F. George

Abstract : The effect of light-induced drift (LID) in gases, predicted by Gel'mukhanov and Shalagin and observed later, is manifested in mechanical drift of the absorbing atoms (molecules) in response to optical excitation. The effect of LID takes place if the atom interaction with light is velocity-dependent (due to the Doppler effect), the spectrum of the exciting radiation is asymmetric with respect to the the absorption line, and the absorbing molecules experience collisions with a buffer gas, with the collision rate dependent upon their internal state. The idea of LID is the following. Suppose for the sake of definiteness that the collision frequency of the absorbing molecules with the buffer is greater in the excited state and that the exciting light is red-shifted with respect to the absorption contour. Then due to the Doppler shift, the radiation interacts mainly with the counter-moving molecules, which undergo transitions into an excited state, in which their friction upon the buffer component is increased. Due to this increase, the counter-flying molecules are slowed down, while the molecules moving in the direction of light are not affected. The net effect is a drift of the absorbing component in the direction of light. The drift alternates its direction with the change of signs of either the detaining or the difference in the collision frequencies.

•May 22, 1992•0 citations

Anomalous light-induced drift of potassium in Ne plus rare-gas mixtures

Frazaneh Yahyaei-Moayyed, Alan D. Streater

We report anomalous light-induced drift of potassium vapor in mixtures of Ne with another rare gas. The drift velocity versus laser frequency curve shows a strong deviation from the dispersion curve predicted by the standard theory of light-induced drift based on velocity-independent collision rates. The observed drift velocity versus frequency curves have three zero-crossings. For a qualitative explanation of the results, a strong collision model with velocity-dependent collision rates is used. The partial pressures that cancel normal light-induced drift also provide accurate ratios of cross section for potassium collisions with the various buffer gases. The observation of anomalous light-induced drift in a simple atomic system offers the opportunity to relate the results to potential curves. \textcopyright{} 1996 The American Physical Society.

Physical Review A•Jun 1, 1996•19 citations

Light-induced drift of barium atoms

Č. Hradečný, J. Slovák, T. Těthal +2 more

An observation of light-induced drift (LID) of atoms with an intermediate metastable level between the ground and excited resonance levels is reported. The drift of atoms of barium was investigated. Molecular nitrogen was used as a buffer gas. The 5d $^{1}$D metastable state of Ba atoms was quenched in collisions with ${\mathrm{N}}_{2}$ molecules. It has been deduced from the experimental results that the collision cross section of Ba atoms with ${\mathrm{N}}_{2}$ molecules is larger for Ba atoms in the ground state than in the 6p $^{1}$P excited state. The maximal LID velocity was about 250 cm/s.

Physical Review A•Apr 1, 1995•4 citations

Study of the optical piston

H. G. C. Werij, Jos E. M. Haverkort, J. P. Woerdman

We report an experimental and theoretical study of the optical piston, a consequence of the phenomenon of light-induced drift (LID), observed in binary mixtures of Na vapor and a buffer gas. Good agreement has been found between experiment and existing theory as far as the shape of the Na density profile in the piston is concerned. The piston velocity is anomalously low; this is accounted for by incorporating the effects of adsorption and desorption into the theory. Furthermore, we introduce a rate-equation model for LID which incorporates the fine and hyperfine structure of the level scheme of the Na absorbers; this gives insight into the sublevel velocity distributions and the nonequilibrium part of the total velocity distribution during LID.

Physical Review A•May 1, 1986•63 citations

White-light-induced drift in a gas with one optically active species

Alan D. Streater

A new light-induced drift effect is discussed in which a white-light source separates a gas mixture containing a single optically active (absorbing) species and a buffer gas which does not interact with the light. A three-level model with one upper level and two closely spaced lower levels is used for the active atoms, and strong collisions with the more abundant surrounding buffer gas atoms are assumed. The intensity spectrum in the vapor (including the effects of hyperfine pumping), and the resulting drift velocity are calculated as a function of optical depth into the vapor.

Physical Review A•Jan 1, 1990•8 citations
Conventional light-induced drift is based on purely elastic velocity-changing collisions. The authors discuss qualitatively the potentialities of light-induced drift originating from inelastic velocity-changing collisions, which may occur in a molecular buffer gas. In such collisions a large fraction of the electronic excitation energy of the absorbing particle may be transformed into kinetic energy thus affecting light-induced drift. The authors report experiments on light-induced drift of Na in various molecular buffer gases and compare these with their predictions.
We present a model for light-induced drift (LID) in the Na--noble-gas system which should enable direct comparison with experiment. In contrast to previous theories of LID based on a two-level description of the optical absorbers and on a simplified collision treatment, the present model is based on a realistic description of laser-driven Na atoms immersed in a buffer gas. Starting from the generalized Bloch equations, we introduce a rate-equation model for the velocity distributions in the four important Na levels. The velocity-changing and fine-structure-changing collisions are described using composite Keilson-Storer collision kernels in which all adjustable parameters have been eliminated by using available literature data. We apply the model in numerical calculations of LID as a function of all experimentally accessible parameters. It is found that the ground-state hyperfine splitting can have large effects on LID, whereas the excited-state fine-structure splitting has not. The paper establishes criteria for optimum LID effects; when using a single-frequency laser the maximum attainable drift velocity is predicted to be 13.8 m/s. Using a proper set of boundary conditions, we find a pressure dependence of LID qualitatively different from the predictions based on previous work. Finally, the influence of the collision model is investigated. We find that LID is independent of the shape of the collision kernel, indicating that a strong-collision model is always valid.
Abstract : The effect of light-induced drift (LID) in gases, predicted by Gel'mukhanov and Shalagin and observed later, is manifested in mechanical drift of the absorbing atoms (molecules) in response to optical excitation. The effect of LID takes place if the atom interaction with light is velocity-dependent (due to the Doppler effect), the spectrum of the exciting radiation is asymmetric with respect to the the absorption line, and the absorbing molecules experience collisions with a buffer gas, with the collision rate dependent upon their internal state. The idea of LID is the following. Suppose for the sake of definiteness that the collision frequency of the absorbing molecules with the buffer is greater in the excited state and that the exciting light is red-shifted with respect to the absorption contour. Then due to the Doppler shift, the radiation interacts mainly with the counter-moving molecules, which undergo transitions into an excited state, in which their friction upon the buffer component is increased. Due to this increase, the counter-flying molecules are slowed down, while the molecules moving in the direction of light are not affected. The net effect is a drift of the absorbing component in the direction of light. The drift alternates its direction with the change of signs of either the detaining or the difference in the collision frequencies.
We report anomalous light-induced drift of potassium vapor in mixtures of Ne with another rare gas. The drift velocity versus laser frequency curve shows a strong deviation from the dispersion curve predicted by the standard theory of light-induced drift based on velocity-independent collision rates. The observed drift velocity versus frequency curves have three zero-crossings. For a qualitative explanation of the results, a strong collision model with velocity-dependent collision rates is used. The partial pressures that cancel normal light-induced drift also provide accurate ratios of cross section for potassium collisions with the various buffer gases. The observation of anomalous light-induced drift in a simple atomic system offers the opportunity to relate the results to potential curves. \textcopyright{} 1996 The American Physical Society.
An observation of light-induced drift (LID) of atoms with an intermediate metastable level between the ground and excited resonance levels is reported. The drift of atoms of barium was investigated. Molecular nitrogen was used as a buffer gas. The 5d 1^{1}1D metastable state of Ba atoms was quenched in collisions with N2{\mathrm{N}}_{2}N2​ molecules. It has been deduced from the experimental results that the collision cross section of Ba atoms with N2{\mathrm{N}}_{2}N2​ molecules is larger for Ba atoms in the ground state than in the 6p 1^{1}1P excited state. The maximal LID velocity was about 250 cm/s.
We report an experimental and theoretical study of the optical piston, a consequence of the phenomenon of light-induced drift (LID), observed in binary mixtures of Na vapor and a buffer gas. Good agreement has been found between experiment and existing theory as far as the shape of the Na density profile in the piston is concerned. The piston velocity is anomalously low; this is accounted for by incorporating the effects of adsorption and desorption into the theory. Furthermore, we introduce a rate-equation model for LID which incorporates the fine and hyperfine structure of the level scheme of the Na absorbers; this gives insight into the sublevel velocity distributions and the nonequilibrium part of the total velocity distribution during LID.
A new light-induced drift effect is discussed in which a white-light source separates a gas mixture containing a single optically active (absorbing) species and a buffer gas which does not interact with the light. A three-level model with one upper level and two closely spaced lower levels is used for the active atoms, and strong collisions with the more abundant surrounding buffer gas atoms are assumed. The intensity spectrum in the vapor (including the effects of hyperfine pumping), and the resulting drift velocity are calculated as a function of optical depth into the vapor.