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:1710.01665 · Physical Review A

Backward-emitted sub-Doppler fluorescence from an optically thick atomic vapor

J. C. de Aquino Carvalho, Athanasios Laliotis, Martine Chevrollier, Marcos Oriá, Daniel Bloch

Published Oct 4, 2017• 8 citations
arXivHTMLPDF

Abstract

Literature mentions only incidentally a sub-Doppler contribution in the excitation spectrum of the backward fluorescence of a dense vapor. This contribution is here investigated on Cs vapor, both on the first resonance line (894 nm) and on the weaker second resonance line (459 nm). We show that in a strongly absorbing medium, the quenching of excited atoms moving towards a window irradiated under near normal incidence reduces the fluorescence on the red side of the excitation spectrum. Atoms moving slowly towards the window produce a sub-Doppler velocity-selective contribution, whose visibility is here improved by applying a frequency-modulation technique. This sub-Doppler feature, induced by a surface quenching combined with a short absorption length for the incident irradiation, exhibits close analogies with the narrow spectra appearing with thin vapor cells. We also show that a normal incidence irradiation is essential for the sub-Doppler feature to be observed, while it should be independent of the detection geometry.

DOI
10.1103/physreva.96.043405

Related papers

Sub-Doppler retrofluorescence from an optically thick atomic vapor

J. C. de Aquino Carvalho, Athanasios Laliotis, Thierry Passerat de Silans +3 more

Sub-Doppler contributions are observed in back-fluorescence spectra of a dense laser-excited atomic vapor. These features have similarities with the narrow contributions observed in fluorescence or in absorption signals of thin vapor cells.

Latin America Optics and Photonics Conference•Jan 1, 2016•1 citation

Sub-Doppler spectroscopy in a thin film of resonant vapor

S. Briaudeau, Daniel Bloch, M. Ducloy

We report on the spectroscopy in a resonant vapor film, in a regime in which the inhomogeneous transit time induces a velocity selection. For cell thickness (10--1000 \ensuremath{\mu}m) smaller than the transverse dimensions and for low enough atomic density, the atomic trajectories are essentially free flights from wall to wall. Hence, a single laser beam irradiation is sufficient to observe sub-Doppler resonances because of the transient atomic response, which enhances the response of the slowest atoms flying nearly parallel to the wall. The peculiar features of this velocity selection are presented in the linear regime as well as in the case of saturation induced by the optical pumping. Also, we report, in the case of the Cs ${D}_{2}$ line (852 nm), on the passage from a two-level linear-response regime to an optical pumping regime when increasing the incident intensity. We also describe the influence of several other parameters, including cell thickness and laser beam size and shape, on the experimental line shapes. An extension to Doppler-free polarization spectroscopy in a thin cell with a single beam, and to saturated absorption, is also reported.

Physical Review A•May 1, 1999•87 citations

Sub-Doppler Spectroscopy of Room-Temperature Cs Atomic Vapor in a 400-nm-Thick Nanocell

Armen D. Sargsyan, Rodolphe Momier, A. Papoyan +1 more

Abstract The sub-Doppler absorption and fluorescence spectra at the frequencies of D1- and D2-line transitions in Cs atomic vapor, enclosed in a nanocell (NC) with a thickness L ~ 400 nm, have been investigated experimentally at a near-room temperature. It is shown that a decrease in the NC temperature to 35°C causes narrowing of the absorption lines to values smaller than the Doppler width by a factor of 6, due to which the strong spectral broadening induced by laser field can be measured. The high intensity threshold for optical pumping (which limits the fluorescence intensity in centimeter-length cells) made it possible to record fluorescence spectra (using laser power of several milliwatts) at a temperature of 20°C; thus, a frequency marker of transitions in the range of D1,2 lines can be developed based on a room-temperature NC. A comparison with a widely used marker based on saturated absorption is performed.

Journal of Experimental and Theoretical Physics•Oct 1, 2021•2 citations

Detection of slow atoms in laser spectroscopy of a thin vapor film

S. Briaudeau, Daniel Bloch, M. Ducloy

We report on high-resolution single-light-beam transmission spectroscopy through an ultra thin vapor cell (thickness 10–100 μm). In addition to the expected Doppler-broadened absorption, a novel sub-Doppler structure is observed under normal incidence irradiation. This structure originates from the optical response of atoms with very small velocity components perpendicular to the cell walls, and is connected with the transient atom excitation regime during the wall-to-wall time of flight. In experiments performed in Cs vapor, the slow mechanism of optical pumping leads, for weak light intensities (10–100 μW/cm 2 ) and a 10 μm cell, to a velocity selection equivalent to an effective 1D temperature in the sub-mK range.

Europhysics Letters (EPL)•Aug 10, 1996•90 citations

Sub-Doppler spectroscopy of cesium vapor layers with nanometric and micrometric thickness

S. Cartaleva, Solomon M. Saltiel, Armen D. Sargsyan +4 more

The saturation behavior of absorption and fluorescence spectra on the D2 line of Cs is presented, demonstrating a significant difference between open and closed transitions. Cs vapor is confined in an extremely thin cell (ETC) with widely tunable thickness L=(0.5-3)λ, where λ is the light wavelength. In the saturation regime, the closed transition demonstrates enhanced absorption in a narrow spectral interval due to the Dicke effect, while the open one demonstrates only a velocity-selective dip in the absorption. The fluorescence of open transitions shows reduced fluorescence dips, enhancing their contrast with ETC thickness. The closed transition exhibits only a small plateau around the optical transition center. Applying two-level theoretical modeling based on optical Bloch equations, a qualitative agreement with experimental observations is achieved. The rate of contrast enhancement with cell thickness is larger for the theoretical than for the experimental dips. In addition, for the closed transition a tiny peak in the fluorescence is theoretically predicted, with the first experimental confirmation presented. The sub-Doppler spectra of vapor layers with a thickness of several light wavelengths show potential for realization of precise frequency references and photonics sensors.

Journal of the Optical Society of America B•Oct 3, 2009•29 citations

Spectral line narrowing due to velocity selective optical pumping on the D2 line hyperfine transitions in spatially restricted Cs vapor

C. Andreeva, T. A. Vartanyan, Petko Todorov +2 more

We report on the investigation of narrow sub-Doppler-width resonances observed at the D2 line of Cs atoms (Fg = 4 → Fe = 3, 4, 5 hyperfine transitions), confined in thin optical cells. These cells have a thickness of L = 6λ (λ = 852 nm) and L = 700 μm, and are irradiated by two narrow-band laser radiations (one with fixed and the other with scanned frequency). We show that for zero frequency detuning of the fixed-frequency laser from the Fg = 4 → Fe = 5 hyperfine transition, its absorption spectrum in the thin cell consists of resonances, centered at the respective hyperfine transitions. The spectral widths of these resonances range from 2 to 20 MHz, and they are characterized by a good contrast and extremely small Doppler background. This spectrum is highly sensitive to the frequency offset of the fixedfrequency laser. The analysis leads to the conclusion that the spatial restriction of Cs vapor suppresses the interaction of the light with atoms with significant velocity component along the direction of the laser beam propagation.

International Conference and School on Quantum Electronics: Laser Physics and Applications•Jan 29, 2019•0 citations
Literature mentions only incidentally a sub-Doppler contribution in the excitation spectrum of the backward fluorescence of a dense vapor. This contribution is here investigated on Cs vapor, both on the first resonance line (894 nm) and on the weaker second resonance line (459 nm). We show that in a strongly absorbing medium, the quenching of excited atoms moving towards a window irradiated under near normal incidence reduces the fluorescence on the red side of the excitation spectrum. Atoms moving slowly towards the window produce a sub-Doppler velocity-selective contribution, whose visibility is here improved by applying a frequency-modulation technique. This sub-Doppler feature, induced by a surface quenching combined with a short absorption length for the incident irradiation, exhibits close analogies with the narrow spectra appearing with thin vapor cells. We also show that a normal incidence irradiation is essential for the sub-Doppler feature to be observed, while it should be independent of the detection geometry.
We report on the spectroscopy in a resonant vapor film, in a regime in which the inhomogeneous transit time induces a velocity selection. For cell thickness (10--1000 \ensuremath{\mu}m) smaller than the transverse dimensions and for low enough atomic density, the atomic trajectories are essentially free flights from wall to wall. Hence, a single laser beam irradiation is sufficient to observe sub-Doppler resonances because of the transient atomic response, which enhances the response of the slowest atoms flying nearly parallel to the wall. The peculiar features of this velocity selection are presented in the linear regime as well as in the case of saturation induced by the optical pumping. Also, we report, in the case of the Cs D2{D}_{2}D2​ line (852 nm), on the passage from a two-level linear-response regime to an optical pumping regime when increasing the incident intensity. We also describe the influence of several other parameters, including cell thickness and laser beam size and shape, on the experimental line shapes. An extension to Doppler-free polarization spectroscopy in a thin cell with a single beam, and to saturated absorption, is also reported.
Abstract The sub-Doppler absorption and fluorescence spectra at the frequencies of D1- and D2-line transitions in Cs atomic vapor, enclosed in a nanocell (NC) with a thickness L ~ 400 nm, have been investigated experimentally at a near-room temperature. It is shown that a decrease in the NC temperature to 35°C causes narrowing of the absorption lines to values smaller than the Doppler width by a factor of 6, due to which the strong spectral broadening induced by laser field can be measured. The high intensity threshold for optical pumping (which limits the fluorescence intensity in centimeter-length cells) made it possible to record fluorescence spectra (using laser power of several milliwatts) at a temperature of 20°C; thus, a frequency marker of transitions in the range of D1,2 lines can be developed based on a room-temperature NC. A comparison with a widely used marker based on saturated absorption is performed.
We report on high-resolution single-light-beam transmission spectroscopy through an ultra thin vapor cell (thickness 10–100 μm). In addition to the expected Doppler-broadened absorption, a novel sub-Doppler structure is observed under normal incidence irradiation. This structure originates from the optical response of atoms with very small velocity components perpendicular to the cell walls, and is connected with the transient atom excitation regime during the wall-to-wall time of flight. In experiments performed in Cs vapor, the slow mechanism of optical pumping leads, for weak light intensities (10–100 μW/cm 2 ) and a 10 μm cell, to a velocity selection equivalent to an effective 1D temperature in the sub-mK range.
The saturation behavior of absorption and fluorescence spectra on the D2 line of Cs is presented, demonstrating a significant difference between open and closed transitions. Cs vapor is confined in an extremely thin cell (ETC) with widely tunable thickness L=(0.5-3)λ, where λ is the light wavelength. In the saturation regime, the closed transition demonstrates enhanced absorption in a narrow spectral interval due to the Dicke effect, while the open one demonstrates only a velocity-selective dip in the absorption. The fluorescence of open transitions shows reduced fluorescence dips, enhancing their contrast with ETC thickness. The closed transition exhibits only a small plateau around the optical transition center. Applying two-level theoretical modeling based on optical Bloch equations, a qualitative agreement with experimental observations is achieved. The rate of contrast enhancement with cell thickness is larger for the theoretical than for the experimental dips. In addition, for the closed transition a tiny peak in the fluorescence is theoretically predicted, with the first experimental confirmation presented. The sub-Doppler spectra of vapor layers with a thickness of several light wavelengths show potential for realization of precise frequency references and photonics sensors.
We report on the investigation of narrow sub-Doppler-width resonances observed at the D2 line of Cs atoms (Fg = 4 → Fe = 3, 4, 5 hyperfine transitions), confined in thin optical cells. These cells have a thickness of L = 6λ (λ = 852 nm) and L = 700 μm, and are irradiated by two narrow-band laser radiations (one with fixed and the other with scanned frequency). We show that for zero frequency detuning of the fixed-frequency laser from the Fg = 4 → Fe = 5 hyperfine transition, its absorption spectrum in the thin cell consists of resonances, centered at the respective hyperfine transitions. The spectral widths of these resonances range from 2 to 20 MHz, and they are characterized by a good contrast and extremely small Doppler background. This spectrum is highly sensitive to the frequency offset of the fixedfrequency laser. The analysis leads to the conclusion that the spatial restriction of Cs vapor suppresses the interaction of the light with atoms with significant velocity component along the direction of the laser beam propagation.