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

Dynamics of coherent optical pumping in a sodium atomic beam

Eugeny Korsunsky, Wolfgang Maichen, Laurentius Windholz

Published Nov 1, 1997• 17 citations
Publisher

Abstract

This work is concerned with the temporal evolution of the coherent population trapping (CPT) process in the case of additional optical pumping to states not contributing to the CPT superposition states. Special attention is paid to the influence of weak external magnetic fields that can change the laser-atom interaction considerably. The theoretical analysis is completed by experimental observations on a sodium atomic beam, which show good agreement with our theory. The results obtained are of importance for a realistic picture of CPT schemes in practical applications.

DOI
10.1103/physreva.56.3908

Related papers

Coherent population trapping on the sodium D_1 line in high magnetic fields

Rhea C. Holler, Ferruccio Renzoni, Laurentius Windholz +1 more

We consider the coherent-population-trapping (CPT) phenomenon in a sodium atomic vapor. The experiment leading to the first observation of CPT is revisited with an improved experimental setup and a larger range of magnetic-field strengths. From the analysis of the ground-state hyperfine splitting as a function of the applied magnetic field, we conclude that we have observed the whole spectrum of dark resonances within the D1 line corresponding to the nonabsorbing coherent superposition of two Zeeman sublevels of two different components of the 32S1/2 level. This was not obvious a priori because the transition probabilities at high magnetic-field strengths, as applied in the experiment, have to be taken into account. The differences in the contrast of the various black lines are explained in terms of pumpings outside the interaction scheme preparing the nonabsorbing state. Possible applications of CPT in high magnetic fields are discussed.

Journal of the Optical Society of America B•Sep 1, 1997•13 citations

Atomic coherence in laser spectroscopy and atom optics

Jung Bog Kim, Han Seb Moon, Hyun Ah Kim

In order to investigate effects of coherent population trapping (CPT) on electromagnetically induced transparency (EIT), we added an external weak magnetic field to identify a quantization axis. The laser beam whose polarization is parallel to the direction of the external magnetic field and the perpendicular laser are coupled to different transitions. CPT generated by two circular polarization components of the strong coupling beam when the polarization was perpendicular to the quantization axis, was competed with (EIT) so that absorption reduction could be larger than the case without CPT. We investigated the mechanism of steady-state light amplification without inversion using an incoherent pumping laser.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 20, 2003•0 citations

Coherent population trapping in a Λ configuration coupled by magnetic dipole interactions

Huidong Kim, Hyok Sang Han, Tai Hyun Yoon +1 more

We report our study on coherent population trapping (CPT) in a $\ensuremath{\Lambda}$ configuration coupled by magnetic dipole interactions. The $\ensuremath{\Lambda}$ configuration is formed by bichromatic radio-frequency fields coupling a pair of Zeeman sublevels in one hyperfine level of an alkali-metal atom to another sublevel in the other hyperfine level. The Zeeman sublevel at the apex is coupled to a state in the $nP$ manifold via an optical transition on one of the spectroscopic $D$ lines to induce optical pumping to a dark state. The configuration is closed without leakage to other Zeeman sublevels. We use lithium atoms in an optical trap for our experimental study. The system allows independent control of the main parameters characterizing CPT, which include the upper-state decay rate and the decoherence rate as well as the Rabi frequencies. By turning off the applied fields, the system is frozen so that its quantum state can be measured precisely. We studied the line shapes and dynamics of the CPT system, and measured the phase relation of the dark superposition state to find excellent agreement with theory. The possible application of the scheme as a method to cool optically trapped atoms below the recoil limit in a manner analogous to velocity-selective coherent population trapping is discussed.

Physical Review A•Mar 10, 2014•7 citations

Enhanced optical pumping using mutually orthogonal magnetic fields for quantum sensing

Sudip Mandal, Raghwinder Singh Grewal, Swarupananda Pradhan

Abstract The atomic population trapped in irrelevant atomic states is a limiting factor for sensors based on laser-atom interaction. Using a bi-chromatic light field along with a specific combination of magnetic fields, we show a significant increase in the amplitude ( i.e. , more than seven times) of a two-photon coherent population trapping (CPT) resonance, which can be effectively used for atomic magnetometry. This increase in amplitude can be explained through enhanced optical pumping via the transfer of population to the relevant Zeeman states. Our experimental observations are consistent with the theoretical calculations carried out for a realistic three-level atomic system using density matrix formalism. We further discuss the optimum condition for enhanced optical pumping by adjusting the ground-state decoherence rate. Enhanced optical pumping through the manipulation of the magnetic field is quite important and is of great interest in the field of quantum technology.

Europhysics Letters (EPL)•Jul 2, 2024•0 citations

Coherent population trapping with losses observed on the Hanle effect of the D1 sodium line

Ferruccio Renzoni, Wolfgang Maichen, Laurentius Windholz +1 more

We consider the coherent-population-trapping phenomenon in a thermal sodium atomic beam. We compare the different coherent-population-trapping schemes that can be established on the ${\mathrm{D}}_{1}$ line using the Zeeman sublevels of a given ground hyperfine state. The coherent-population-trapping preparation is examined by means of a Hanle-effect configuration. The efficiency of the coherent-population-trapping phenomenon has been examined in presence of optical pumping into hyperfine levels external to those of the excited transition. We show that both the contrast and the width of the coherent population trapping resonance strongly decrease when the optical pumping rate is increased. In the experiment, the loss rate due to optical pumping has been controlled by means of a laser repump of variable intensity.

Physical Review A•May 1, 1997•154 citations

Coherent Population Trapping with Losses on the Sodium D1 Line Hanle Effect

Ferruccio Renzoni, Wolfgang Maichen, Laurentius Windholz +1 more

We consider the coherent population trapping phenomenon in a thermal sodium atomic beam. We compare the different coherent population trapping schemes that can be established on the D1 line using the Zeeman sublevels of a given ground hyperfine state. The coherent population trapping preparation is examined by means of a Hanle effect configuration. The efficiency of the coherent population trapping phenomenon has been examined in presence of optical pumping into hyperfine levels external to those of the excited transition. We show that both the contrast and the width of the coherent population trapping resonance strongly decrease when the optical pumping rate is increased. In the experiment, the loss rate due to optical pumping has been controlled by means of a laser repump of variable intensity.

arXiv:physics/9611007•Nov 10, 1996•0 citations
This work is concerned with the temporal evolution of the coherent population trapping (CPT) process in the case of additional optical pumping to states not contributing to the CPT superposition states. Special attention is paid to the influence of weak external magnetic fields that can change the laser-atom interaction considerably. The theoretical analysis is completed by experimental observations on a sodium atomic beam, which show good agreement with our theory. The results obtained are of importance for a realistic picture of CPT schemes in practical applications.
We consider the coherent-population-trapping (CPT) phenomenon in a sodium atomic vapor. The experiment leading to the first observation of CPT is revisited with an improved experimental setup and a larger range of magnetic-field strengths. From the analysis of the ground-state hyperfine splitting as a function of the applied magnetic field, we conclude that we have observed the whole spectrum of dark resonances within the D1 line corresponding to the nonabsorbing coherent superposition of two Zeeman sublevels of two different components of the 32S1/2 level. This was not obvious a priori because the transition probabilities at high magnetic-field strengths, as applied in the experiment, have to be taken into account. The differences in the contrast of the various black lines are explained in terms of pumpings outside the interaction scheme preparing the nonabsorbing state. Possible applications of CPT in high magnetic fields are discussed.
In order to investigate effects of coherent population trapping (CPT) on electromagnetically induced transparency (EIT), we added an external weak magnetic field to identify a quantization axis. The laser beam whose polarization is parallel to the direction of the external magnetic field and the perpendicular laser are coupled to different transitions. CPT generated by two circular polarization components of the strong coupling beam when the polarization was perpendicular to the quantization axis, was competed with (EIT) so that absorption reduction could be larger than the case without CPT. We investigated the mechanism of steady-state light amplification without inversion using an incoherent pumping laser.
We report our study on coherent population trapping (CPT) in a $\ensuremath{\Lambda}$ configuration coupled by magnetic dipole interactions. The $\ensuremath{\Lambda}$ configuration is formed by bichromatic radio-frequency fields coupling a pair of Zeeman sublevels in one hyperfine level of an alkali-metal atom to another sublevel in the other hyperfine level. The Zeeman sublevel at the apex is coupled to a state in the nPnPnP manifold via an optical transition on one of the spectroscopic DDD lines to induce optical pumping to a dark state. The configuration is closed without leakage to other Zeeman sublevels. We use lithium atoms in an optical trap for our experimental study. The system allows independent control of the main parameters characterizing CPT, which include the upper-state decay rate and the decoherence rate as well as the Rabi frequencies. By turning off the applied fields, the system is frozen so that its quantum state can be measured precisely. We studied the line shapes and dynamics of the CPT system, and measured the phase relation of the dark superposition state to find excellent agreement with theory. The possible application of the scheme as a method to cool optically trapped atoms below the recoil limit in a manner analogous to velocity-selective coherent population trapping is discussed.
Abstract The atomic population trapped in irrelevant atomic states is a limiting factor for sensors based on laser-atom interaction. Using a bi-chromatic light field along with a specific combination of magnetic fields, we show a significant increase in the amplitude ( i.e. , more than seven times) of a two-photon coherent population trapping (CPT) resonance, which can be effectively used for atomic magnetometry. This increase in amplitude can be explained through enhanced optical pumping via the transfer of population to the relevant Zeeman states. Our experimental observations are consistent with the theoretical calculations carried out for a realistic three-level atomic system using density matrix formalism. We further discuss the optimum condition for enhanced optical pumping by adjusting the ground-state decoherence rate. Enhanced optical pumping through the manipulation of the magnetic field is quite important and is of great interest in the field of quantum technology.
We consider the coherent-population-trapping phenomenon in a thermal sodium atomic beam. We compare the different coherent-population-trapping schemes that can be established on the D1{\mathrm{D}}_{1}D1​ line using the Zeeman sublevels of a given ground hyperfine state. The coherent-population-trapping preparation is examined by means of a Hanle-effect configuration. The efficiency of the coherent-population-trapping phenomenon has been examined in presence of optical pumping into hyperfine levels external to those of the excited transition. We show that both the contrast and the width of the coherent population trapping resonance strongly decrease when the optical pumping rate is increased. In the experiment, the loss rate due to optical pumping has been controlled by means of a laser repump of variable intensity.
We consider the coherent population trapping phenomenon in a thermal sodium atomic beam. We compare the different coherent population trapping schemes that can be established on the D1 line using the Zeeman sublevels of a given ground hyperfine state. The coherent population trapping preparation is examined by means of a Hanle effect configuration. The efficiency of the coherent population trapping phenomenon has been examined in presence of optical pumping into hyperfine levels external to those of the excited transition. We show that both the contrast and the width of the coherent population trapping resonance strongly decrease when the optical pumping rate is increased. In the experiment, the loss rate due to optical pumping has been controlled by means of a laser repump of variable intensity.