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

Soviet Journal of Quantum Electronics

Nonlinear spectroscopy within a Doppler profile based on "competitive" resonances

Vladilen S Letokhov, B. D. Pavlik

Published Nov 30, 1975• 0 citations
Publisher

Abstract

An analysis is made of the width and resolution of power resonances in a ring gas laser with a nonlinearly absorbing cell in the resonator. It is shown that in the case of the Lorentzian profile of an inverted Lamb dip in a nonlinearly absorbing cell the resolution of competitive resonances is equal to the homogeneous linewidth in spite of the fact that the width of competitive resonances is much smaller than the homogeneous width (Lamb dip width). An analysis is made of the narrowing of the tip of the Lamb dip in the case of long-lived molecular levels and particularly of the field broadening of the narrowed tip. It is found that the resolution of competitive resonances in the case of a narrowed tip of a Lamb dip in a low-pressure gas cell may be much higher than the resolution governed by the time needed to cross a light beam by molecules with an average thermal velocity.

DOI
10.1070/qe1975v004n11abeh011875

Related papers

Narrowing of sub-Doppler saturated-absorption resonances in multilayer gas cells

А. Ч. Измайлов

We have studied theoretically nontrivial specific features of sub-Doppler resonances of saturated absorption in a multilayer gas cell with a rarefied gas medium, which is a compact analog of a large number of plane-parallel atomic beams. Spatially separated saturating and probing monochromatic laser beams that co- and counterpropagate (at the same frequency) in this cell have been considered. In this situation, the action of the light radiation of the saturating beam on the probing beam is determined by optically pumped atoms that fly between the beams under conditions that the longitudinal components of their velocities experience selection due to a specific geometry of the multilayer cell. Such a selection leads to a narrowing of the sub-Doppler resonance in the absorption of the probing beam and decreases the difference between the structures of this resonance for the cases of co- and counterpropagation of the saturating radiation. We have found that, in the considered multilayer cell, the effective width of the sub-Doppler resonance can be smaller (by a factor of about 1.5) than the extremely narrow characteristic width of the well-known Lamb dip in spectroscopy of saturated absorption in the standard gas cell. Results of this study can be used in atomic spectroscopy of ultrahigh resolution and for the laser-frequency stabilization.

Optics and Spectroscopy•Jul 1, 2014•0 citations

Theory of the nonlinear Ramsey resonance in the optical part of the spectrum

B Ya Dubetskiĭ

It is shown that the interaction of three standing-wave light beams with a low-pressure gas gives rise to a narrow absorption power resonance. The width of this resonance is related to the transit time of gas atoms between the beams. The weak-field case is analyzed. A formula for a Held of arbitrary intensity is obtained for the situation when the dimensions of the beams are much smaller than the distances between them. Numerical calculations are reported of the resonance amplitude and profile. Optimal (in respect of the field intensity) conditions for the observation of the effect are determined. If the distances between the beams are sufficiently large, it should be possible to observe resonances of width equal to the homogeneous width of atomic radiation lines in spite of the considerable field and transit broadening. The possibility of using this power resonance in stabilization of the emission frequency of gas lasers is considered.

Soviet Journal of Quantum Electronics•Jun 30, 1976•11 citations

Collision broadening in Lamb-dip spectroscopy

Lewis S. Klein, Michel Giraud, A. Ben‐Reuven

A previously developed diagrammatic method for calculating the nonlinear response of a dilute gas at near resonance with strong classical radiation fields is extended to include velocity-dependent homogeneous and inhomogeneous broadening phenomena. The method is applied to two-level saturated-absorption (Lamb-dip) spectroscopy. Expressions are obtained for the collision-broadened Lamb dip probed by a weak field in the presence of an arbitrarily strong saturating field and are compared to the usual infinite-Doppler-width, weak-saturation expression. We study the effects of velocity and momentum transfer on the line-shape parameters and discuss the effect of phase-changing and strong inelastic collisions on the intensity.

Physical Review A•Jul 1, 1977•9 citations

Resonance phenomena in saturation of absorption by laser radiation

Vladilen S Letokhov, V. P. Chebotaev

The review deals with resonance phenomena resulting from saturation of low-pressure-gas absorption lines by a coherent optical field, when the spectral lines are inhomogeneously broadened by the Doppler effect. Principal attention is paid to narrow resonances of width much smaller than the Doppler widths, which are produced upon saturation of the absorption by light waves under various experimental conditions (inside and outside the laser resonator, in traveling and standing waves, in spatially separated waves, etc.), owing to different effects (absorption saturation, mode interaction in the laser). Each of the phenomena is considered from both the theoretical and the experimental points of view. The phenomena considered serve as a basis of a new branch of optical spectroscopy, namely nonlinear laser spectroscopy of ultrahigh resolution.

Soviet Physics Uspekhi•Apr 30, 1975•9 citations

Field broadening and shifts of nonlinear power resonances in low-pressure gases

Семибаламут Владимир Михайлович, Е. А. Титов

A calculation is made of the absorption coefficient of a standing-wave field in a gas of two-level molecules allowing for transit effects to within the second order of the saturation parameter. The rate of the field broadening of a nonlinear power resonance is investigated for various dimensions of a light beam. An analysis is also made of the rates of the field shift of the maximum of such a nonlinear resonance because of the quadratic Doppler effect and hyperfine structure of the line.

Soviet Journal of Quantum Electronics•Jul 31, 1978•0 citations

Transit effects in the theory of a Lamb dip in a strong field at very low gas pressures

Alexandre N. Titov

A theoretical analysis is made of the interaction of a spatially bounded plane standing optical wave with a molecular gas at a very low pressure. This theory applies to weak and strong (saturating) fields. Calculations are made of the profile, amplitude, and width of a Lamp dip as a function of the intensity of the saturating field and of the dimensions of the light beam. The role of slow molecules in the formation of the dip is identified. It is shown that in weak saturating fields the width of the resonance is governed by the average thermal velocity of molecules in a gas and by the transverse size of the light beam.

Soviet Journal of Quantum Electronics•May 31, 1985•1 citation
An analysis is made of the width and resolution of power resonances in a ring gas laser with a nonlinearly absorbing cell in the resonator. It is shown that in the case of the Lorentzian profile of an inverted Lamb dip in a nonlinearly absorbing cell the resolution of competitive resonances is equal to the homogeneous linewidth in spite of the fact that the width of competitive resonances is much smaller than the homogeneous width (Lamb dip width). An analysis is made of the narrowing of the tip of the Lamb dip in the case of long-lived molecular levels and particularly of the field broadening of the narrowed tip. It is found that the resolution of competitive resonances in the case of a narrowed tip of a Lamb dip in a low-pressure gas cell may be much higher than the resolution governed by the time needed to cross a light beam by molecules with an average thermal velocity.
We have studied theoretically nontrivial specific features of sub-Doppler resonances of saturated absorption in a multilayer gas cell with a rarefied gas medium, which is a compact analog of a large number of plane-parallel atomic beams. Spatially separated saturating and probing monochromatic laser beams that co- and counterpropagate (at the same frequency) in this cell have been considered. In this situation, the action of the light radiation of the saturating beam on the probing beam is determined by optically pumped atoms that fly between the beams under conditions that the longitudinal components of their velocities experience selection due to a specific geometry of the multilayer cell. Such a selection leads to a narrowing of the sub-Doppler resonance in the absorption of the probing beam and decreases the difference between the structures of this resonance for the cases of co- and counterpropagation of the saturating radiation. We have found that, in the considered multilayer cell, the effective width of the sub-Doppler resonance can be smaller (by a factor of about 1.5) than the extremely narrow characteristic width of the well-known Lamb dip in spectroscopy of saturated absorption in the standard gas cell. Results of this study can be used in atomic spectroscopy of ultrahigh resolution and for the laser-frequency stabilization.
It is shown that the interaction of three standing-wave light beams with a low-pressure gas gives rise to a narrow absorption power resonance. The width of this resonance is related to the transit time of gas atoms between the beams. The weak-field case is analyzed. A formula for a Held of arbitrary intensity is obtained for the situation when the dimensions of the beams are much smaller than the distances between them. Numerical calculations are reported of the resonance amplitude and profile. Optimal (in respect of the field intensity) conditions for the observation of the effect are determined. If the distances between the beams are sufficiently large, it should be possible to observe resonances of width equal to the homogeneous width of atomic radiation lines in spite of the considerable field and transit broadening. The possibility of using this power resonance in stabilization of the emission frequency of gas lasers is considered.
A previously developed diagrammatic method for calculating the nonlinear response of a dilute gas at near resonance with strong classical radiation fields is extended to include velocity-dependent homogeneous and inhomogeneous broadening phenomena. The method is applied to two-level saturated-absorption (Lamb-dip) spectroscopy. Expressions are obtained for the collision-broadened Lamb dip probed by a weak field in the presence of an arbitrarily strong saturating field and are compared to the usual infinite-Doppler-width, weak-saturation expression. We study the effects of velocity and momentum transfer on the line-shape parameters and discuss the effect of phase-changing and strong inelastic collisions on the intensity.
The review deals with resonance phenomena resulting from saturation of low-pressure-gas absorption lines by a coherent optical field, when the spectral lines are inhomogeneously broadened by the Doppler effect. Principal attention is paid to narrow resonances of width much smaller than the Doppler widths, which are produced upon saturation of the absorption by light waves under various experimental conditions (inside and outside the laser resonator, in traveling and standing waves, in spatially separated waves, etc.), owing to different effects (absorption saturation, mode interaction in the laser). Each of the phenomena is considered from both the theoretical and the experimental points of view. The phenomena considered serve as a basis of a new branch of optical spectroscopy, namely nonlinear laser spectroscopy of ultrahigh resolution.
A theoretical analysis is made of the interaction of a spatially bounded plane standing optical wave with a molecular gas at a very low pressure. This theory applies to weak and strong (saturating) fields. Calculations are made of the profile, amplitude, and width of a Lamp dip as a function of the intensity of the saturating field and of the dimensions of the light beam. The role of slow molecules in the formation of the dip is identified. It is shown that in weak saturating fields the width of the resonance is governed by the average thermal velocity of molecules in a gas and by the transverse size of the light beam.