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

arXiv:2311.12606 · Physical Review A

Multiphoton quantum interference in precision spectroscopic experiments

Dmitry A. Solovyev, Timur A. Zalialiutdinov, A. Anikin, Leonti N Labzowsky

Published May 2, 2024• 3 citations
arXivHTMLPDF

Abstract

Modern resonance spectroscopic experiments on the measurement of transition frequencies in atoms have reached a level where a meticulous description of all aspects of the studied processes has become obligatory. The precision achieved has led to the fact that the determination of the transition frequency on the basis of measured data is substantially refined by theoretical treatment of the observed spectral line profile. Thus, a large impact of effects arising beyond the resonance approximation, in particular due to the effect of quantum interference, is found experimentally. We show that the picture becomes even more complicated when the observed spectral line profile is ``identified'' with one of the processes---emission or absorption. An accurate determination of the transition frequency requires a description of the absorption line profile inseparable from the emission process, and vice versa. The theoretical aspects discussed in this paper create prerequisites for more accurate experiments.

DOI
10.1103/physreva.109.052802

Related papers

Impact of quantum interference in cascade radiation on the absorption profile

Dmitry A. Solovyev, A. Anikin, Timur A. Zalialiutdinov +1 more

Spectroscopic measurements of transition frequencies in various atomic systems are a significant part of modern physics. They enable the testing of fundamental interactions, the determination of physical constants, and the study of fundamental symmetries that occur in nature with unprecedented accuracy. Studies based on two-photon spectroscopy of simple atoms represent some of the most accurate experiments to date. The verification of precision experimental results is largely supported by theoretical analysis, which is most rigorous for light, nonrelativistic atoms and ions. In the last decade, much attention in the literature has been paid to the study of the quantum interference effect (QIE) in hydrogen and hydrogenlike atomic systems. This has made it possible to significantly reduce the experimental error in determining the appropriate transition frequency. The theoretical description of the QIE corresponds to the consideration of similar pathways arising for close-lying resonant states into which the transition frequency is measured. In the present work, the influence of the emission process on the absorption profile formation is investigated. The results of the studies carried out in this work show the need to take into account the effect of quantum interference in cascade radiation for the precise determination of the absorption transition frequency to highly excited states in two-photon spectroscopic experiments.

Physical Review A•Feb 9, 2024•4 citations

Evaluation of the influence of neighboring resonance on spectroscopy measurements

Ming-Chen Chen, Xiao-Qiu Qi, Aixi Chen

The quantum interference arising from neighboring resonance is investigated in a four-level system. This effect is evaluated through two methods: one is the direct numerical solution of the optical Bloch equation, and the other considers the impact of neighboring resonances as perturbations on other equations, i.e., using a simplified approximate optical Bloch equation for simulation. The results show that the energy shift caused by quantum interference is correlated with the spectral separation of two resonances, and is most significant when the interval is comparable to the spontaneous emission rate [Formula: see text]. For spectral separation that is sufficiently large, with spacing greater than [Formula: see text], the approximate optical Bloch equation method proves to be a straightforward and efficient approach. In addition, two formulas are given, which can be used to evaluate the contributions of neighboring resonances at other positions once the contribution of one is determined. According to the formulas, we evaluated the result of 4He atom as about [Formula: see text] kHz, which is consistent with the value given in the paper [Phys. Rev. A 86 (2012) 040501(R)]. Utilizing these methods can streamline intricate energy level structures, and thus facilitate the evaluation of quantum interference in high-precision spectroscopic measurements.

Modern Physics Letters B•Feb 28, 2024•0 citations

Observation of quantum interference of optical transition pathways in Doppler-free two-photon spectroscopy and implications for precision measurements

Bubai Rahaman, Sid C. Wright, Sourav Dutta

Doppler-free two-photon (DFTP) spectroscopy is a standard technique for precision measurement of transition frequencies of dipole-forbidden transitions. Here, we report the observation of quantum interference (QI) of optical transition pathways in DFTP spectroscopy of the cesium $6S\text{\ensuremath{-}}7D$ transitions chosen as a prototype system. The QI manifests itself as asymmetric line shapes of the hyperfine lines of the $7D$ states, observed through spontaneous emission following excitation by a narrow-linewidth cw laser. The interference persists despite the lines being spectrally well resolved. Ignoring the effect and fitting the spectrum to a Voigt profile causes large systematic shifts in the determination of the line centers, while accounting for QI resolves the apparent line shift and enables the precise determination of hyperfine splitting in the $7D$ states. We calculate the spectral line shape including the effect of QI and show that it agrees with the experimental observations. Our results are broadly applicable to other species and have implications for portable secondary optical clocks and precision measurements of hyperfine splittings, isotope shifts, and transition frequencies.

arXiv:2308.12386•Physical Review A•Apr 22, 2024•7 citations

Two-Photon Quantum Interference Polarization Spectroscopy: Measurements of Transition Matrix Elements in Atomic Rubidium

A. I. Beger

The estimation of the adequacy of theoretical calculations on the atomic structure requires availability of the precise experimental data on radiative properties of the atoms. Such data is also required in astronomy and some important areas of technology. The lack of precision of traditional spectroscopic studies of atom presents a fundamental obstacle for progress in these areas. For example, in atomic rubidium, the best precision of the traditional spectroscopic results is on the order of about 1 - 5%, which does not allow for clear assessment of the latest sophisticated theoretical calculations on atomic rubidium structure, with emphasis on different, in nature, effects. This situation is typical for atomic physics in general. The purpose of present study is obtaining the experimental data on the radiative properties of atomic rubidium with precision considerably higher than that of the traditional spectroscopic methods. This is accomplished by means of the two-photon quantum interference polarization spectroscopy. A two-photon polarization spectrum of the rubidium atom is obtained in the range of detunings -417 cm-1 to +99 cm-1 from atomic 5s2S1/2-5p 2P3/2-*8s2S1/2resonance. From analysis of the spectra the relativistic and many body effects on the wavefiinctions are revealed in the form of a uniquely defined parameter q = 2 x 10-6 (5) cm and an exact relation between parameters R and p which quantitatively describes the process: R = 1.01756 (57) + 81.466 (15) p where R is dimensionless and p is in cm. The obtained results can be thought of as specific experimentally established two-photon sum rules and can be used for testing the accuracy of the theoretical wavefiinctions. The experimental technique has important advantages comparing to some traditional spectroscopic methods and is essentially free of systematic effects.

•Sep 25, 2019•0 citations

Interference spectra in a two-level atom

Constantine Mavroyannis

We have considered the interference spectra arising from the competition between a spontaneous process and one induced by a laser field in a two-level atom. Expressions for the spectral functions have been derived describing the spectra of the excited and ground states of the atom in the low- and high-intensity limit of the laser field. For the excited-state spectra in the low-intensity limit, the frequency profiles of the two peaks, which arise from the spontaneous and the induced processes, cancel each other out completely near the center of the line, while for the ground state the induced process dominates. For finite values of the detuning, the spectra of the excited state consist of two peaks, which have positive and negative frequency profiles, respectively. The computed spectra have been graphically presented and discussed. In the high-intensity limit, the dynamic Stark effect dominates the spectra of the excited and ground states of the atom. Expressions for the correlation functions have been derived that describe the emission or the absorption of a laser photon at two different times. The derived expressions for the corresponding delay functions in the low- and high-intensity limits have been found to be identical to those recently proposed in the literature. The laser field has been treated as a classical as well as a quantized entity.

Canadian Journal of Physics•Dec 1, 1990•6 citations

Quantum interference effects in saturated absorption spectroscopy of n=2 triplet-helium fine structure

A. Marsman, Marko Horbatsch, Eric A. Hessels

The effects of quantum-mechanical interference with a far-off-resonant transition on saturated-absorption measurements of atomic fine-structure intervals are found to be substantially larger than measurement uncertainty, and it is shown how properly taking them into account brings several previous measurements into agreement.

Physical Review A•Jun 22, 2015•27 citations
Modern resonance spectroscopic experiments on the measurement of transition frequencies in atoms have reached a level where a meticulous description of all aspects of the studied processes has become obligatory. The precision achieved has led to the fact that the determination of the transition frequency on the basis of measured data is substantially refined by theoretical treatment of the observed spectral line profile. Thus, a large impact of effects arising beyond the resonance approximation, in particular due to the effect of quantum interference, is found experimentally. We show that the picture becomes even more complicated when the observed spectral line profile is ``identified'' with one of the processes---emission or absorption. An accurate determination of the transition frequency requires a description of the absorption line profile inseparable from the emission process, and vice versa. The theoretical aspects discussed in this paper create prerequisites for more accurate experiments.
Spectroscopic measurements of transition frequencies in various atomic systems are a significant part of modern physics. They enable the testing of fundamental interactions, the determination of physical constants, and the study of fundamental symmetries that occur in nature with unprecedented accuracy. Studies based on two-photon spectroscopy of simple atoms represent some of the most accurate experiments to date. The verification of precision experimental results is largely supported by theoretical analysis, which is most rigorous for light, nonrelativistic atoms and ions. In the last decade, much attention in the literature has been paid to the study of the quantum interference effect (QIE) in hydrogen and hydrogenlike atomic systems. This has made it possible to significantly reduce the experimental error in determining the appropriate transition frequency. The theoretical description of the QIE corresponds to the consideration of similar pathways arising for close-lying resonant states into which the transition frequency is measured. In the present work, the influence of the emission process on the absorption profile formation is investigated. The results of the studies carried out in this work show the need to take into account the effect of quantum interference in cascade radiation for the precise determination of the absorption transition frequency to highly excited states in two-photon spectroscopic experiments.
The quantum interference arising from neighboring resonance is investigated in a four-level system. This effect is evaluated through two methods: one is the direct numerical solution of the optical Bloch equation, and the other considers the impact of neighboring resonances as perturbations on other equations, i.e., using a simplified approximate optical Bloch equation for simulation. The results show that the energy shift caused by quantum interference is correlated with the spectral separation of two resonances, and is most significant when the interval is comparable to the spontaneous emission rate [Formula: see text]. For spectral separation that is sufficiently large, with spacing greater than [Formula: see text], the approximate optical Bloch equation method proves to be a straightforward and efficient approach. In addition, two formulas are given, which can be used to evaluate the contributions of neighboring resonances at other positions once the contribution of one is determined. According to the formulas, we evaluated the result of 4He atom as about [Formula: see text] kHz, which is consistent with the value given in the paper [Phys. Rev. A 86 (2012) 040501(R)]. Utilizing these methods can streamline intricate energy level structures, and thus facilitate the evaluation of quantum interference in high-precision spectroscopic measurements.
Doppler-free two-photon (DFTP) spectroscopy is a standard technique for precision measurement of transition frequencies of dipole-forbidden transitions. Here, we report the observation of quantum interference (QI) of optical transition pathways in DFTP spectroscopy of the cesium $6S\text{\ensuremath{-}}7D$ transitions chosen as a prototype system. The QI manifests itself as asymmetric line shapes of the hyperfine lines of the 7D7D7D states, observed through spontaneous emission following excitation by a narrow-linewidth cw laser. The interference persists despite the lines being spectrally well resolved. Ignoring the effect and fitting the spectrum to a Voigt profile causes large systematic shifts in the determination of the line centers, while accounting for QI resolves the apparent line shift and enables the precise determination of hyperfine splitting in the 7D7D7D states. We calculate the spectral line shape including the effect of QI and show that it agrees with the experimental observations. Our results are broadly applicable to other species and have implications for portable secondary optical clocks and precision measurements of hyperfine splittings, isotope shifts, and transition frequencies.
The estimation of the adequacy of theoretical calculations on the atomic structure requires availability of the precise experimental data on radiative properties of the atoms. Such data is also required in astronomy and some important areas of technology. The lack of precision of traditional spectroscopic studies of atom presents a fundamental obstacle for progress in these areas. For example, in atomic rubidium, the best precision of the traditional spectroscopic results is on the order of about 1 - 5%, which does not allow for clear assessment of the latest sophisticated theoretical calculations on atomic rubidium structure, with emphasis on different, in nature, effects. This situation is typical for atomic physics in general. The purpose of present study is obtaining the experimental data on the radiative properties of atomic rubidium with precision considerably higher than that of the traditional spectroscopic methods. This is accomplished by means of the two-photon quantum interference polarization spectroscopy. A two-photon polarization spectrum of the rubidium atom is obtained in the range of detunings -417 cm-1 to +99 cm-1 from atomic 5s2S1/2-5p 2P3/2-*8s2S1/2resonance. From analysis of the spectra the relativistic and many body effects on the wavefiinctions are revealed in the form of a uniquely defined parameter q = 2 x 10-6 (5) cm and an exact relation between parameters R and p which quantitatively describes the process: R = 1.01756 (57) + 81.466 (15) p where R is dimensionless and p is in cm. The obtained results can be thought of as specific experimentally established two-photon sum rules and can be used for testing the accuracy of the theoretical wavefiinctions. The experimental technique has important advantages comparing to some traditional spectroscopic methods and is essentially free of systematic effects.
We have considered the interference spectra arising from the competition between a spontaneous process and one induced by a laser field in a two-level atom. Expressions for the spectral functions have been derived describing the spectra of the excited and ground states of the atom in the low- and high-intensity limit of the laser field. For the excited-state spectra in the low-intensity limit, the frequency profiles of the two peaks, which arise from the spontaneous and the induced processes, cancel each other out completely near the center of the line, while for the ground state the induced process dominates. For finite values of the detuning, the spectra of the excited state consist of two peaks, which have positive and negative frequency profiles, respectively. The computed spectra have been graphically presented and discussed. In the high-intensity limit, the dynamic Stark effect dominates the spectra of the excited and ground states of the atom. Expressions for the correlation functions have been derived that describe the emission or the absorption of a laser photon at two different times. The derived expressions for the corresponding delay functions in the low- and high-intensity limits have been found to be identical to those recently proposed in the literature. The laser field has been treated as a classical as well as a quantized entity.