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

Journal of Physics Conference Series

Polarization dependence of two-photon excitation of cold 7Li Rydberg atoms

Sergey A. Saakyan, Andrey A. Bobrov, E V Vilshanskaya, Vladimir A. Sautenkov, Boris B. Zelener

Published Jan 1, 2019• 0 citations
Publisher

Abstract

The two-photon excitation of cold 7 Li atoms at the 2 S –120 S transition is studied with variable polarization of one of the two counter-propagating optical beams. The maximum efficiency of the two-photon transfer of atoms from the ground state 2 S to the Rydberg state 120 S can be reached when the circular polarizations of the beams are orthogonal. In this case the selection rules Δ L = 0 are satisfied. By using a rotating quarter-wave plate it is possible to vary the polarization of the selected optical beam and change the amplitude of the two-photon resonance. The recorded dependence of the two-photon resonance on the beam polarization is discussed. The obtained results can be used to compensate the unwanted variations of the beam polarization after reflections from mirrors.

DOI
10.1088/1742-6596/1147/1/012096

Related papers

Two-photon Rydberg resonances in lithium-7 obtained by recording reduction of resonance fluorescence

Boris B. Zelener, Sergey A. Saakyan, Vladimir A. Sautenkov +1 more

In a magneto-optical trap (MOT) of 7Li, two-photon Rydberg resonances are recorded by using a spectroscopic technique, which based on variation in the resonance fluorescence. The first excitation frequency is detuned by 0.59 GHz from the intermediate 2P 3/2 state. Two counter-propagating laser beams are used. The resonances are studied on two-photon transitions 2S 1/2 − nl in a range of principal quantum number n from 38 to 120. The widths of the observed resonances are varied from 4.4 to 13 MHz for different MOT parameters.

Doklady Physics•Mar 1, 2017•1 citation

Polarization rotation effects in atomic sodium vapor

P. F. Liao, Gary C. Bjorklund

Polarization rotation effects in atomic sodium vapor are studied both experimentally and theoretically. Two pulsed dye laser beams propagate collinearly through a cell containing sodium vapor. The direction of polarization of a linearly polarized dye laser beam of frequency ${\ensuremath{\omega}}_{1}$ is found to be rotated by a circularly polarized beam of frequency ${\ensuremath{\omega}}_{2}$. This rotation is due to the difference in refractive index at ${\ensuremath{\omega}}_{1}$ for right and left circularly polarized light which is produced by the circularly polarized beam. When ${\ensuremath{\omega}}_{1}+{\ensuremath{\omega}}_{2}$ is tuned near the $3S\ensuremath{-}5S$ two-photon transition of atomic sodium, this difference is primarily due to the dispersion associated with the two-photon transition. Other sources of polarization rotation which were identified include (i) real transfers of population to excited atomic levels due to collisionally induced transitions and (ii) optically induced atomic energy-level shifts. The theory includes both the effects of two-photon dispersion and optically induced energy shifts. The application of the two-photon polarization rotation effect as a fast, optically controlled shutter or modulator and as a sensitive detection technique for two-photon spectroscopy are briefly discussed.

Physical Review A•May 1, 1977•59 citations

Real-time detection of Rydberg excitation dynamics of cold atoms in an optical cavity

Elmer Suarez, Sebastian Slama

We report on the real-time detection of internal-state dynamics of cold Rubidium atoms being excited from the ground state to the $30D_{5/2}$ Rydberg state via two-photon excitation in a ladder-type system. The atoms are first trapped and then released from a magneto-optic trap (MOT) positioned inside the mode of a low-finesse cavity. Then, Rydberg excitation is performed by a simultaneous pulse from two counter-propagating laser beams transverse to the cavity axis. This excitation changes the number of atoms able to absorb or emit cavity photons; thus, changing the collective atom-cavity coupling. We detect this by weakly driving the cavity and collecting the light transmitted through it with an avalanche photodiode (APD). We are able to observe not only the 2-photon excitation dynamics, but also the transfer of population out of the Rydberg state due to black-body radiation (BBR) and the decay back to the ground state.

•Sep 30, 2021•0 citations

Differential two-photon spectroscopy for nondestructive temperature measurements of cold light atoms in a magneto-optical trap

Vladimir A. Sautenkov, Sergey A. Saakyan, Andrey A. Bobrov +3 more

A differential two-photon spectroscopic technique for measurement of atomic temperatures in a working magneto-optical trap was demonstrated. We performed experimental and theoretical studies of two-photon resonances on Rydberg transitions 2S1/2−2P3/2−58S in cold Li7 atoms by using counter- and co-propagating laser beams. By analyzing the spectral shapes, a dependence of Rabi broadening and Doppler broadening on total intensity of cooling laser beams was obtained. We measured the temperature of Li7 atoms in the range from 0.25 to 0.75 mK. Our theoretical and experimental results are in reasonably good agreement. The developed approach for temperature measurements can be applied to cold atoms in different traps, including confined hydrogen and antihydrogen atoms.

Journal of the Optical Society of America B•Jun 6, 2018•17 citations

Two-photon excitation of ultracold atoms to Rydberg states

Sergey A. Saakyan, Vladimir A. Sautenkov, E V Vilshanskaya +2 more

In this work, we discuss two-photon excitation and diagnostic of ultracold Rydberg atoms in a magneto-optical trap. Lithium atoms were excited by using ultraviolet cw laser. For identification of Rydberg transitions, we recorded resonance fluorescence of ultracold atoms. Spectra of transitions 2P- n S, 2p- n D were measured. Our results are in good agreement with calculations and experimental data available in literature. Presented work is a part of our project focused on preparation and study of Rydberg matter and ultracold plasma.

Journal of Physics Conference Series•Nov 11, 2015•2 citations

Circular dichroism in atomic resonance-enhanced few-photon ionization

A. H. N. C. De Silva, T. Moon, K. L. Romans +8 more

We investigate few-photon ionization of lithium atoms prepared in the polarized $2p\phantom{\rule{0.16em}{0ex}}({m}_{\ensuremath{\ell}}=+1)$ state when subjected to femtosecond light pulses with left- or right-handed circular polarization at wavelengths between 665 and 920 nm. We consider whether ionization proceeds more favorably for the electric field co- or counter-rotating with the initial electronic current density. Strong asymmetries are found and quantitatively analyzed in terms of ``circular dichroism'' (CD). While the intensity dependence of the measured CD values is rather weak throughout the investigated regime, a very strong sensitivity on the center wavelength of the incoming radiation is observed. While the co-rotating situation overall prevails, the counter-rotating geometry is strongly favored around 800 nm due to the $2p\text{\ensuremath{-}}3s$ resonant transition, which can only be driven by counter-rotating fields. The observed features provide insights into the helicity dependence of light-atom interactions, and on the possible control of electron emission in atomic few-photon ionization by polarization-selective resonance enhancement.

arXiv:2103.07499•Physical Review A•May 28, 2021•24 citations
The two-photon excitation of cold 7 Li atoms at the 2 S –120 S transition is studied with variable polarization of one of the two counter-propagating optical beams. The maximum efficiency of the two-photon transfer of atoms from the ground state 2 S to the Rydberg state 120 S can be reached when the circular polarizations of the beams are orthogonal. In this case the selection rules Δ L = 0 are satisfied. By using a rotating quarter-wave plate it is possible to vary the polarization of the selected optical beam and change the amplitude of the two-photon resonance. The recorded dependence of the two-photon resonance on the beam polarization is discussed. The obtained results can be used to compensate the unwanted variations of the beam polarization after reflections from mirrors.
In a magneto-optical trap (MOT) of 7Li, two-photon Rydberg resonances are recorded by using a spectroscopic technique, which based on variation in the resonance fluorescence. The first excitation frequency is detuned by 0.59 GHz from the intermediate 2P 3/2 state. Two counter-propagating laser beams are used. The resonances are studied on two-photon transitions 2S 1/2 − nl in a range of principal quantum number n from 38 to 120. The widths of the observed resonances are varied from 4.4 to 13 MHz for different MOT parameters.
Polarization rotation effects in atomic sodium vapor are studied both experimentally and theoretically. Two pulsed dye laser beams propagate collinearly through a cell containing sodium vapor. The direction of polarization of a linearly polarized dye laser beam of frequency ${\ensuremath{\omega}}_{1}$ is found to be rotated by a circularly polarized beam of frequency ${\ensuremath{\omega}}_{2}$. This rotation is due to the difference in refractive index at ${\ensuremath{\omega}}_{1}$ for right and left circularly polarized light which is produced by the circularly polarized beam. When ${\ensuremath{\omega}}_{1}+{\ensuremath{\omega}}_{2}$ is tuned near the $3S\ensuremath{-}5S$ two-photon transition of atomic sodium, this difference is primarily due to the dispersion associated with the two-photon transition. Other sources of polarization rotation which were identified include (i) real transfers of population to excited atomic levels due to collisionally induced transitions and (ii) optically induced atomic energy-level shifts. The theory includes both the effects of two-photon dispersion and optically induced energy shifts. The application of the two-photon polarization rotation effect as a fast, optically controlled shutter or modulator and as a sensitive detection technique for two-photon spectroscopy are briefly discussed.
We report on the real-time detection of internal-state dynamics of cold Rubidium atoms being excited from the ground state to the 30D5/230D_{5/2}30D5/2​ Rydberg state via two-photon excitation in a ladder-type system. The atoms are first trapped and then released from a magneto-optic trap (MOT) positioned inside the mode of a low-finesse cavity. Then, Rydberg excitation is performed by a simultaneous pulse from two counter-propagating laser beams transverse to the cavity axis. This excitation changes the number of atoms able to absorb or emit cavity photons; thus, changing the collective atom-cavity coupling. We detect this by weakly driving the cavity and collecting the light transmitted through it with an avalanche photodiode (APD). We are able to observe not only the 2-photon excitation dynamics, but also the transfer of population out of the Rydberg state due to black-body radiation (BBR) and the decay back to the ground state.
A differential two-photon spectroscopic technique for measurement of atomic temperatures in a working magneto-optical trap was demonstrated. We performed experimental and theoretical studies of two-photon resonances on Rydberg transitions 2S1/2−2P3/2−58S in cold Li7 atoms by using counter- and co-propagating laser beams. By analyzing the spectral shapes, a dependence of Rabi broadening and Doppler broadening on total intensity of cooling laser beams was obtained. We measured the temperature of Li7 atoms in the range from 0.25 to 0.75 mK. Our theoretical and experimental results are in reasonably good agreement. The developed approach for temperature measurements can be applied to cold atoms in different traps, including confined hydrogen and antihydrogen atoms.
In this work, we discuss two-photon excitation and diagnostic of ultracold Rydberg atoms in a magneto-optical trap. Lithium atoms were excited by using ultraviolet cw laser. For identification of Rydberg transitions, we recorded resonance fluorescence of ultracold atoms. Spectra of transitions 2P- n S, 2p- n D were measured. Our results are in good agreement with calculations and experimental data available in literature. Presented work is a part of our project focused on preparation and study of Rydberg matter and ultracold plasma.
We investigate few-photon ionization of lithium atoms prepared in the polarized $2p\phantom{\rule{0.16em}{0ex}}({m}_{\ensuremath{\ell}}=+1)$ state when subjected to femtosecond light pulses with left- or right-handed circular polarization at wavelengths between 665 and 920 nm. We consider whether ionization proceeds more favorably for the electric field co- or counter-rotating with the initial electronic current density. Strong asymmetries are found and quantitatively analyzed in terms of ``circular dichroism'' (CD). While the intensity dependence of the measured CD values is rather weak throughout the investigated regime, a very strong sensitivity on the center wavelength of the incoming radiation is observed. While the co-rotating situation overall prevails, the counter-rotating geometry is strongly favored around 800 nm due to the $2p\text{\ensuremath{-}}3s$ resonant transition, which can only be driven by counter-rotating fields. The observed features provide insights into the helicity dependence of light-atom interactions, and on the possible control of electron emission in atomic few-photon ionization by polarization-selective resonance enhancement.