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 A

Complete quenching of fluorescence from a two-level atom driven by a weak, narrow-band, nonclassical light field

William Smyth, S. Swain

Published Apr 1, 1999• 12 citations
Publisher

Abstract

We consider a two-level atom driven by an ideal degenerate optical parametric oscillator. For squeezing bandwidths of the order of the natural width $\ensuremath{\gamma},$ and smaller, we report remarkable spectral profiles for the scattered light. We also consider a system where the atom is driven by arbitrarily correlated light of arbitrary bandwidth. Employing analytic and numerical solutions, we find different spectral features depending on the classical or nonclassical nature of the driving field. The spectral linewidth can be both subnatural and narrower than the incident field linewidth, an effect that does not require nonclassical light. However, nonclassical light is essential for the appearance of a narrow hole at line center. It is a unique signature of the quantum nature of the field, and for ideal squeezing, the fluorescence at line center vanishes.

DOI
10.1103/physreva.59.r2579

Related papers

Fluorescence quenching and spectral narrowing from a two-level atom driven by a weak, narrow band, light field

William Smyth, S. Swain

We consider a single two-level atom driven by the output from a degenerate optical parametric oscillator. For squeezing bandwidths of the order of the natural atomic width and smaller, we report remarkable spectral profiles for the scattered light, including the existence of a narrow hole at line-centre. Under appropriate conditions, the spectrum may be both subnatural and narrower than the spectrum of the incident field, a phenomenon which does not depend upon strong coupling. To explain the role of the classical or non-classical nature of the driving field plays, we consider an alternative system which enables the atom to be driven by an arbitrary bandwidth light field with arbitrary two-photon correlations. Both numerical and analytic solutions are employed to provide physical insight. Surprisingly, spectral narrowing does not require squeezing: narrowed spectra appear for driving with a blackbody field. Then the atomic fluorescence can be expressed as the product of the atomic response with the incident spectrum. The resulting narrowing is maximized for incident bandwidths of the order of the natural width. However, the narrow hole at line-centre does require a non-classical driving field. For ideal squeezing, the fluorescence at line-centre vanishes. We test how robust the effects are to changes in experimentally pertinent factors such as the solid angle of coupling.

Journal of Modern Optics•Jul 1, 1999•1 citation

Two-level atom in an optical parametric oscillator: Spectra of transmitted and fluorescent fields in the weak-driving-field limit

James Clemens, Perry R. Rice, P. K. Rungta +1 more

We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak-driving-field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even in the strong-coupling limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a subnatural linewidth may occur. These effects disappear for larger driving fields, unlike the spectral narrowing obtained in resonance fluorescence in a squeezed vacuum; here it is important that the squeezing parameter N tends to zero so that the system interacts with only one correlated pair of photons at a time. We show that a previous explanation for spectral narrowing and spectral holes for incoherent scattering is not applicable in the present case, and propose an alternative explanation. We attribute these anomalous effects to quantum interference in the two-photon scattering of the system.

arXiv:quant-ph/9907093•Physical Review A•Aug 8, 2000•14 citations

Response of a two-level atom to a narrow-bandwidth squeezed-vacuum excitation

Azeddine Messikh, R. Tanaś, Z. Ficek

Using the coupled-system approach we calculate the optical spectra of the fluorescence and transmitted fields of a two-level atom driven by a squeezed vacuum of bandwidths smaller than the natural atomic linewidth. We find that in this regime of squeezing bandwidths the spectra exhibit unique features, such as a hole burning and a three-peak structure, which do not appear for a broadband excitation. We show that the features are unique to the quantum nature of the driving squeezed vacuum field and do not appear when the atom is driven by a classically squeezed field. We find that a quantum squeezed-vacuum field produces squeezing in the emitted fluorescence field which appears only in the squeezing spectrum while there is no squeezing in the total field. We also discuss a nonresonant excitation and find that depending on the squeezing bandwidth there is a peak or a hole in the spectrum at a frequency corresponding to a three-wave-mixing process. The hole appears only for a broadband excitation and results from the strong correlations between squeezed-vacuum photons.

Physical Review A•Feb 15, 2000•14 citations

Nonclassical effects in optical spectra

Perry R. Rice, H. J. Carmichael

The incoherent part of the Mollow spectrum for resonance fluorescence has a subnatural linewidth in the weak-field limit. We show that this is due to squeezing of the fluctuations in the induced atomic dipole. The reduced linewidth persists for driving field intensities of approximately 12% of the saturation intensity, where Rabi sidebands begin to appear. We find a similar linewidth narrowing in the transmitted and fluorescent spectra for a single atom in a weakly driven resonant cavity. In this system single-quantum frequency splitting can produce a two-peaked spectrum. Both peaks have a narrowed linewidth. The spectrum of the transmitted light shows a second nonclassical effect that is due to squeezing. A spectral hole may appear at line center, giving a two-peaked spectrum even when there is no frequency splitting.

Journal of the Optical Society of America B•Aug 1, 1988•68 citations

Single-atom fluorescence with nonclassical light

Irina E. Lyublinskaya, Reeta Vyas

The statistical properties of fluorescent light from a single two-level atom driven by nonclassical light beams that exhibit antibunching and squeezing are discussed in the weak-field limit. The fields produced in intracavity second-harmonic generation and those produced by superposing the light from a degenerate parametric oscillator with a coherent field are considered to be the models of nonclassical light beams. These fields can be described in terms of real Gaussian random processes with nonzero mean coherent components. Analytical expressions for the fluorescent light intensity, the second-order intensity correlation function, and the variance of the photon number in the steady state are obtained. The effects of driving-field correlations, detuning, and other parameters characterizing the atom-field interaction on the statistics of scattered light are investigated. It is found that for a certain range of parameters the second-order intensity correlation function may vanish at nonzero times. Under certain other circumstances the antibunching of the fluorescent photons is enhanced. These and other interesting features that appear in the scattered light are discussed.

Physical Review A•Nov 1, 1993•10 citations

Resonance fluorescence of a two-level atom in a two-mode squeezed vacuum

A. S. Parkins

The dynamics of a strongly driven two-level atom are examined for the case that the atom is coupled to a ``two-mode'' squeezed vacuum. The source of squeezed light is taken to be a (frequency) nondegenerate parametric oscillator. We consider the situation in which the Rabi sidebands produced by the coherent driving field coincide with the spectral peaks of the parametric oscillator. Approximate analytical results are presented and checked against numerical simulations of the exact equations. For a suitable choice of relative phase, all three spectral lines in the fluorescence triplet are found to exhibit subnatural linewidths. Significant modifications to the fluorescence spectrum are also possible with a nonzero laser-atom detuning.

Physical Review A•Dec 1, 1990•44 citations
We consider a two-level atom driven by an ideal degenerate optical parametric oscillator. For squeezing bandwidths of the order of the natural width \ensuremathγ,\ensuremath{\gamma},\ensuremathγ, and smaller, we report remarkable spectral profiles for the scattered light. We also consider a system where the atom is driven by arbitrarily correlated light of arbitrary bandwidth. Employing analytic and numerical solutions, we find different spectral features depending on the classical or nonclassical nature of the driving field. The spectral linewidth can be both subnatural and narrower than the incident field linewidth, an effect that does not require nonclassical light. However, nonclassical light is essential for the appearance of a narrow hole at line center. It is a unique signature of the quantum nature of the field, and for ideal squeezing, the fluorescence at line center vanishes.
We consider a single two-level atom driven by the output from a degenerate optical parametric oscillator. For squeezing bandwidths of the order of the natural atomic width and smaller, we report remarkable spectral profiles for the scattered light, including the existence of a narrow hole at line-centre. Under appropriate conditions, the spectrum may be both subnatural and narrower than the spectrum of the incident field, a phenomenon which does not depend upon strong coupling. To explain the role of the classical or non-classical nature of the driving field plays, we consider an alternative system which enables the atom to be driven by an arbitrary bandwidth light field with arbitrary two-photon correlations. Both numerical and analytic solutions are employed to provide physical insight. Surprisingly, spectral narrowing does not require squeezing: narrowed spectra appear for driving with a blackbody field. Then the atomic fluorescence can be expressed as the product of the atomic response with the incident spectrum. The resulting narrowing is maximized for incident bandwidths of the order of the natural width. However, the narrow hole at line-centre does require a non-classical driving field. For ideal squeezing, the fluorescence at line-centre vanishes. We test how robust the effects are to changes in experimentally pertinent factors such as the solid angle of coupling.
We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak-driving-field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even in the strong-coupling limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a subnatural linewidth may occur. These effects disappear for larger driving fields, unlike the spectral narrowing obtained in resonance fluorescence in a squeezed vacuum; here it is important that the squeezing parameter N tends to zero so that the system interacts with only one correlated pair of photons at a time. We show that a previous explanation for spectral narrowing and spectral holes for incoherent scattering is not applicable in the present case, and propose an alternative explanation. We attribute these anomalous effects to quantum interference in the two-photon scattering of the system.
Using the coupled-system approach we calculate the optical spectra of the fluorescence and transmitted fields of a two-level atom driven by a squeezed vacuum of bandwidths smaller than the natural atomic linewidth. We find that in this regime of squeezing bandwidths the spectra exhibit unique features, such as a hole burning and a three-peak structure, which do not appear for a broadband excitation. We show that the features are unique to the quantum nature of the driving squeezed vacuum field and do not appear when the atom is driven by a classically squeezed field. We find that a quantum squeezed-vacuum field produces squeezing in the emitted fluorescence field which appears only in the squeezing spectrum while there is no squeezing in the total field. We also discuss a nonresonant excitation and find that depending on the squeezing bandwidth there is a peak or a hole in the spectrum at a frequency corresponding to a three-wave-mixing process. The hole appears only for a broadband excitation and results from the strong correlations between squeezed-vacuum photons.
The incoherent part of the Mollow spectrum for resonance fluorescence has a subnatural linewidth in the weak-field limit. We show that this is due to squeezing of the fluctuations in the induced atomic dipole. The reduced linewidth persists for driving field intensities of approximately 12% of the saturation intensity, where Rabi sidebands begin to appear. We find a similar linewidth narrowing in the transmitted and fluorescent spectra for a single atom in a weakly driven resonant cavity. In this system single-quantum frequency splitting can produce a two-peaked spectrum. Both peaks have a narrowed linewidth. The spectrum of the transmitted light shows a second nonclassical effect that is due to squeezing. A spectral hole may appear at line center, giving a two-peaked spectrum even when there is no frequency splitting.
The statistical properties of fluorescent light from a single two-level atom driven by nonclassical light beams that exhibit antibunching and squeezing are discussed in the weak-field limit. The fields produced in intracavity second-harmonic generation and those produced by superposing the light from a degenerate parametric oscillator with a coherent field are considered to be the models of nonclassical light beams. These fields can be described in terms of real Gaussian random processes with nonzero mean coherent components. Analytical expressions for the fluorescent light intensity, the second-order intensity correlation function, and the variance of the photon number in the steady state are obtained. The effects of driving-field correlations, detuning, and other parameters characterizing the atom-field interaction on the statistics of scattered light are investigated. It is found that for a certain range of parameters the second-order intensity correlation function may vanish at nonzero times. Under certain other circumstances the antibunching of the fluorescent photons is enhanced. These and other interesting features that appear in the scattered light are discussed.
The dynamics of a strongly driven two-level atom are examined for the case that the atom is coupled to a ``two-mode'' squeezed vacuum. The source of squeezed light is taken to be a (frequency) nondegenerate parametric oscillator. We consider the situation in which the Rabi sidebands produced by the coherent driving field coincide with the spectral peaks of the parametric oscillator. Approximate analytical results are presented and checked against numerical simulations of the exact equations. For a suitable choice of relative phase, all three spectral lines in the fluorescence triplet are found to exhibit subnatural linewidths. Significant modifications to the fluorescence spectrum are also possible with a nonzero laser-atom detuning.