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

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Strong field effects in spectroscopy of degenerated metastable atoms

I. A. Kartashov, Sergei G Rautian, A. V. Shishaev

Published Oct 21, 1998• 0 citations
Publisher

Abstract

In the introduced paper the results of theoretical and experimental investigations in a branch of probe-field spectroscopy of degenerated metastable atoms in a laser radiation field of arbitrary intensity with taking into account of its anisotropical excitation and the presence of additional channels of radiant decay of upper level are presented. It is shown that for the degenerated levels which are excited anisotropically the absorption spectrum of the probe field contains, besides resonances caused by occupancy effects, resonances associated with the magnetic coherence and manifested in the form of peaks and dips with substantially different amplitudes and widths. A fundamentally new property of these resonances is that their widths are proportional to the intensity of the orienting field, and the amplitude of the narrowest resonance becomes appreciable when the orienting field is very strong.

DOI
10.1117/12.328237

Related papers

Probe field spectroscopy in two-level systems with arbitrary phase memory in collisions

А. И. Пархоменко, Anatolii M. Shalagin

The spectrum of weak probe field absorption (amplification) by two-level atoms experiencing collisions with buffer gas atoms in a strong resonance laser field is studied theoretically. Analysis is carried out for systems with a weak Doppler broadening under relatively mild constraints on the strong field intensity for the general case of an arbitrary change in the phase of the radiation-induced dipole moment in elastic collisions of gas particles. It is shown that, in spite of uniform broadening of the absorption line, the probe field spectrum exhibits a clearly manifested anisotropy to mutual orientation of the wavevectors of strong and probe radiation. It is found that the width of resonances in the probe field spectrum under definite conditions (that can easily be created in experiments) is proportional to the diffusion coefficient for atoms interacting with radiation. This fact can form the basis of the spectroscopic method for measuring the transport frequencies of collisions between particles absorbing radiation and buffer particles. It is shown that phase memory effects in collisions strongly modify the probe field spectrum both qualitatively and quantitatively. Simple operative formulas proposed for the probe field spectrum are convenient for experimental data processing.

Journal of Experimental and Theoretical Physics•Feb 1, 2005•4 citations

Magnetic coherence effects in the spectroscopy of transitions between energy levels with total angular momenta J = 1/2 and J = 1 using unidirectional waves

Э. Г. Сапрыкин, А. А. Черненко

Abstract The physical processes that form the spectra of saturated absorption resonances at atomic transitions between energy levels with angular momenta J = 1/2 and J = 1 in the field of two unidirectional linearly polarised laser waves are studied analytically and numerically. It is shown that the specific features of the resonance spectra are formed in the Λ-schemes of transitions and manifest themselves in the form of narrow coherent structures – dips due to the magnetic coherence (optical orientation) of the transition levels induced by the optical fields. In this case, the energy levels of the lower state make the main contribution, and the contribution of the transfer of magnetic coherence from the sublevels of the upper state to the lower ones in the resonance amplitude manifests itself as an additive. Conditions are found under which the nonlinear resonance is exclusively coherent. The effect of the saturating wave field on the shape of coherent resonance structures is studied.

Quantum Electronics•Jun 1, 2022•1 citation

The influence of higher spatial harmonics of atomic polarization on the saturated absorption resonance upon excitation of open dipole transitions by a field of counterpropagating waves

Denis V. Brazhnikov, A. S. Novokreshchenov

The effect of a double structure of saturated absorption resonance in the field of counterpropagating light waves interacting with an atomic gas is studied. The experimental observation of this effect was first reported in 2011 in a work by our colleagues at the P.N. Lebedev Physical Institute of the Russian Academy of Sciences (Laboratory of Frequency Standards). The essence of the effect lies in the fact that, on exciting an open dipole transition, another, narrower, resonance of an opposite sign can be observed at the center of the ordinary saturated absorption resonance. A theoretical analysis of this effect has also been performed in this work in terms of a simple spectroscopic model of an atom with two nondegenerate energy levels without taking into account higher spatial harmonics of atomic polarization and polarizations of light waves (scalar model). The present work is devoted to the development of a theory of the formation of a central narrow resonance for the example of a real F g = 1 → F e = 1 atomic transition and to the study of its main characteristics (amplitude, width, contrast, and amplitude-to-width ratio). In addition, the theoretical results obtained without taking into account the influence of higher spatial harmonics and with inclusion of the influence of first higher harmonics are compared. This comparison shows that their influence on the parameters of the new nonlinear resonance is strong even in moderately intense light fields (R ~ γ, where R is the Rabi frequency). The results of this study can be of interest for quantum metrology, as well as for many experiments in which the laser-radiation frequency is stabilized by the saturated absorption resonance on open dipole transitions in atoms and molecules.

Optics and Spectroscopy•Apr 1, 2017•1 citation

Coherent two-field spectroscopy of degenerate two-level systems

A. Lezama

Spectroscopic features revealing the coherent interaction of a degenerate two-level atomic system with two optical fields are examined. A model for the numerical calculation of the response of a degenerate two-level system to the action of an arbitrarily intense resonant pump field and a weak probe in the presence of a magnetic field is presented. The model is valid for arbitrary values of the total angular momentum of the lower and upper levels and for any choice of the polarizations of the optical waves. Closed and open degenerate two-level systems are considered. Predictions for probe absorption and dispersion, field generation by four-wave-mixing, population modulation and Zeeman optical pumping are derived. On all these observables, sub-natural-width coherence resonances are predicted and their spectroscopic features are discussed. Experimental spectra for probe absorption and excited state population modulation in the D2 line of Rb vapor are presented in good agreement with the calculations

arXiv:quant-ph/9907002•Jul 1, 1999•0 citations

Coherent two-field spectroscopy of degenerate two-level systems

A. Lezama, S. Barreiro, A. Lipsich +1 more

Spectroscopic features revealing the coherent interaction of a degenerate two-level atomic system with two optical fields are examined. A model for the numerical calculation of the response of a degenerate two-level system to the action of an arbitrarily intense resonant pump field and a weak probe in the presence of a magnetic field is presented. The model is valid for arbitrary values of the total angular momentum of the lower and upper levels and for any choice of the polarizations of the optical waves. Closed and open degenerate two-level systems are considered. Predictions for probe absorption and dispersion, field generation by four-wave mixing, population modulation, and Zeeman optical pumping are derived. On all these observables, subnatural-width coherence resonances are predicted and their spectroscopic features are discussed. Experimental spectra for probe absorption and excited-state population modulation in the ${D}_{2}$ line of Rb vapor are presented in good agreement with the calculations.

Physical Review A•Dec 8, 1999•87 citations

Effects of Saturation and Self-Saturation in Unidirectional-Wave Spectroscopy of Transition between Levels with a Total Moment of J = 1

Э. Г. Сапрыкин, А. А. Черненко

Abstract Nonlinear absorption of a probe field in a system of degenerate levels of an atom characterized by a total moment of J = 1 in unidirectional waves is studied analytically and numerically taking into account saturation by its own spontaneous emission (OSE). The trends in changes of the amplitude and frequency characteristics of the nonlinear resonance associated with open and closed types of transitions for different polarizations of the waves that are introduced by self-saturation are established. Specific manifestations of the effect, including those related to magnetic coherence of levels, are revealed.

Optics and Spectroscopy•Oct 1, 2019•2 citations
In the introduced paper the results of theoretical and experimental investigations in a branch of probe-field spectroscopy of degenerated metastable atoms in a laser radiation field of arbitrary intensity with taking into account of its anisotropical excitation and the presence of additional channels of radiant decay of upper level are presented. It is shown that for the degenerated levels which are excited anisotropically the absorption spectrum of the probe field contains, besides resonances caused by occupancy effects, resonances associated with the magnetic coherence and manifested in the form of peaks and dips with substantially different amplitudes and widths. A fundamentally new property of these resonances is that their widths are proportional to the intensity of the orienting field, and the amplitude of the narrowest resonance becomes appreciable when the orienting field is very strong.
The spectrum of weak probe field absorption (amplification) by two-level atoms experiencing collisions with buffer gas atoms in a strong resonance laser field is studied theoretically. Analysis is carried out for systems with a weak Doppler broadening under relatively mild constraints on the strong field intensity for the general case of an arbitrary change in the phase of the radiation-induced dipole moment in elastic collisions of gas particles. It is shown that, in spite of uniform broadening of the absorption line, the probe field spectrum exhibits a clearly manifested anisotropy to mutual orientation of the wavevectors of strong and probe radiation. It is found that the width of resonances in the probe field spectrum under definite conditions (that can easily be created in experiments) is proportional to the diffusion coefficient for atoms interacting with radiation. This fact can form the basis of the spectroscopic method for measuring the transport frequencies of collisions between particles absorbing radiation and buffer particles. It is shown that phase memory effects in collisions strongly modify the probe field spectrum both qualitatively and quantitatively. Simple operative formulas proposed for the probe field spectrum are convenient for experimental data processing.
Abstract The physical processes that form the spectra of saturated absorption resonances at atomic transitions between energy levels with angular momenta J = 1/2 and J = 1 in the field of two unidirectional linearly polarised laser waves are studied analytically and numerically. It is shown that the specific features of the resonance spectra are formed in the Λ-schemes of transitions and manifest themselves in the form of narrow coherent structures – dips due to the magnetic coherence (optical orientation) of the transition levels induced by the optical fields. In this case, the energy levels of the lower state make the main contribution, and the contribution of the transfer of magnetic coherence from the sublevels of the upper state to the lower ones in the resonance amplitude manifests itself as an additive. Conditions are found under which the nonlinear resonance is exclusively coherent. The effect of the saturating wave field on the shape of coherent resonance structures is studied.
The effect of a double structure of saturated absorption resonance in the field of counterpropagating light waves interacting with an atomic gas is studied. The experimental observation of this effect was first reported in 2011 in a work by our colleagues at the P.N. Lebedev Physical Institute of the Russian Academy of Sciences (Laboratory of Frequency Standards). The essence of the effect lies in the fact that, on exciting an open dipole transition, another, narrower, resonance of an opposite sign can be observed at the center of the ordinary saturated absorption resonance. A theoretical analysis of this effect has also been performed in this work in terms of a simple spectroscopic model of an atom with two nondegenerate energy levels without taking into account higher spatial harmonics of atomic polarization and polarizations of light waves (scalar model). The present work is devoted to the development of a theory of the formation of a central narrow resonance for the example of a real F g = 1 → F e = 1 atomic transition and to the study of its main characteristics (amplitude, width, contrast, and amplitude-to-width ratio). In addition, the theoretical results obtained without taking into account the influence of higher spatial harmonics and with inclusion of the influence of first higher harmonics are compared. This comparison shows that their influence on the parameters of the new nonlinear resonance is strong even in moderately intense light fields (R ~ γ, where R is the Rabi frequency). The results of this study can be of interest for quantum metrology, as well as for many experiments in which the laser-radiation frequency is stabilized by the saturated absorption resonance on open dipole transitions in atoms and molecules.
Spectroscopic features revealing the coherent interaction of a degenerate two-level atomic system with two optical fields are examined. A model for the numerical calculation of the response of a degenerate two-level system to the action of an arbitrarily intense resonant pump field and a weak probe in the presence of a magnetic field is presented. The model is valid for arbitrary values of the total angular momentum of the lower and upper levels and for any choice of the polarizations of the optical waves. Closed and open degenerate two-level systems are considered. Predictions for probe absorption and dispersion, field generation by four-wave-mixing, population modulation and Zeeman optical pumping are derived. On all these observables, sub-natural-width coherence resonances are predicted and their spectroscopic features are discussed. Experimental spectra for probe absorption and excited state population modulation in the D2 line of Rb vapor are presented in good agreement with the calculations
Spectroscopic features revealing the coherent interaction of a degenerate two-level atomic system with two optical fields are examined. A model for the numerical calculation of the response of a degenerate two-level system to the action of an arbitrarily intense resonant pump field and a weak probe in the presence of a magnetic field is presented. The model is valid for arbitrary values of the total angular momentum of the lower and upper levels and for any choice of the polarizations of the optical waves. Closed and open degenerate two-level systems are considered. Predictions for probe absorption and dispersion, field generation by four-wave mixing, population modulation, and Zeeman optical pumping are derived. On all these observables, subnatural-width coherence resonances are predicted and their spectroscopic features are discussed. Experimental spectra for probe absorption and excited-state population modulation in the D2{D}_{2}D2​ line of Rb vapor are presented in good agreement with the calculations.
Abstract Nonlinear absorption of a probe field in a system of degenerate levels of an atom characterized by a total moment of J = 1 in unidirectional waves is studied analytically and numerically taking into account saturation by its own spontaneous emission (OSE). The trends in changes of the amplitude and frequency characteristics of the nonlinear resonance associated with open and closed types of transitions for different polarizations of the waves that are introduced by self-saturation are established. Specific manifestations of the effect, including those related to magnetic coherence of levels, are revealed.