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 B Atomic Molecular and Optical Physics

Rectified optical force on dark-state atoms

Eugeny Korsunsky, Dmitry V. Kosachiov

Published Dec 28, 1997• 4 citations
Publisher

Abstract

We show that an imperfection of velocity-selective coherent population trapping (VSCPT) in three-level atoms excited by standing light waves causes a rectified force on cooled atoms. The rectified force as well as the cooling force are calculated both analytically and numerically for and cascade three-level systems. Combination of these forces with the VSCPT mechanism can lead to localization of very cold atoms in potential wells created by the rectified force. This effect should be taken into account in experiments with VSCPT in standing waves, and can be used for realizing superlattices of cold atoms, in particular, cold Rydberg atoms.

DOI
10.1088/0953-4075/30/24/010

Related papers

How to produce very cold Rydberg atoms

Eugeny Korsunsky, Yuri V. Rozhdestvenskii

We show that an ensemble of atoms in highly excited states with narrow center-of-mass momentum distribution (cold Rydberg atoms) can be obtained with velocity-selective (pi) - pulses and laser cooling by velocity-selective coherent population trapping (VSCPT). Both methods use three-level cascade systems with the uppermost state being the Rydberg one where the atoms are excited and cooled. Very high fraction of atoms can be cooled to subrecoil temperatures by the use of VSCPT in standing light waves.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 6, 1996•0 citations

Force in velocity-selective coherent population trapping: Full quantum-mechanical description

Norbert Leinfellner, Eugeny Korsunsky, Laurentius Windholz

ABSTRACT In this work we present an investigation of velocity-selective coherent population trapping (VSCPT) in asym- metric three-level schemes. The light force in such schemes is of an intrinsically transient character and shouldnot be described in a quasiclassical approach. Instead, results of the full quantum-mechanical calculations are presented with emphasis on their meaning to the efficiency of subrecoil laser cooling. 1 INTRODUCTION Laser cooling of neutral atoms has received significant advances by the introduction of velocity-selectivecoherent population trapping ((VSCPT) some years ago.1 Since it leads to atomic temperatures well below therecoil limit, studies of ultracold atoms and atomic interactions may be improved by magnitudes.The effect of VSCPT relies on optical pumping of atoms into a state WNC) which is a trap state for a certaincenter-of-mass velocity vO. This trap state is created by a destructive superposition of atomic states within amultilevel quantum system. Once being in such a state LWNC) the laser light does not interact anymore with theatom which leads to a decoupling with the rest of the system at vo. Atoms located outside this small velocityregion get a chance to be trapped by the momentum diffusion due to spontaneous emission of photons. Aftera sufficient long interaction time nearly all atoms are trapped inside a narrow momentum distribution whichcan be interpreted as cooling. The theoretical and experimental investigation of VSCPT is usually consideredby use of a three-level A-system as shown in Fig.1. Such a system can be found for example in a symmetrical

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jan 1, 1996•0 citations

Laser cooling of Rydberg atoms by velocity-selective coherent population trapping

Jingzhong Guo, Eugeny Korsunsky, E. Arimondo

One-dimensional velocity-selective coherent population trapping (VSCPT) in a cascade atomic configuration, with the second excited level a Rydberg state, is investigated through numerical calculations. The trapping efficiency for the case of travelling wave lasers is derived from the solution of the optical Bloch equations. For excitation by bichromatic standing waves, the energy-band approach is applied. Although the cooling process is limited by the spontaneous emission decay of the Rydberg state, the coexistence of polarization-gradient cooling and VSCPT in the case of standing waves allows the preparation of the majority of the atomic population in a cold Rydberg state.

Quantum and Semiclassical Optics Journal of the European Optical Society Part B•Jun 1, 1996•3 citations

Velocity-selective coherent population trapping in conjunction with pol-grad cooling in a folded three-level system under standing wave excitation

D. P. Katz, M. S. Shahriar, Philip Hemmer +2 more

We identify the conditions under which velocity selective coherent population trapping (VSCPT) takes place when a three level Λ system is excited by a pair of Raman resonant standing waves.

Annual Meeting Optical Society of America•Jan 1, 1993•0 citations

Observation of three-level rectified dipole forces acting on trapped atoms

Timothy T. Grove, B. C. Duncan, V. Sánchez-Villicaña +1 more

We have observed rectified dipole forces acting on three-level atoms in the cascade configuration. Laser cooled and trapped rubidium atoms are illuminated with an intense bichromatic standing wave (780 and 776 nm) tuned near resonance with the 5${\mathit{S}}_{1/2}$\ensuremath{\rightarrow}5${\mathit{P}}_{3/2}$\ensuremath{\rightarrow}5${\mathit{D}}_{5/2}$ transitions. The resulting rectified forces produce periodic potential wells (71-\ensuremath{\mu}m period), which localize the cold atoms. Experimental results are in reasonable agreement with theoretical predictions. These forces may be useful in atom optics and laser traps.

Physical Review A•Jun 1, 1995•29 citations

Force-assisted velocity selective coherent population trapping

H Wu, G. Hillenbrand, Giovanna Morigi +1 more

We present a fully quantum analysis of velocity selective coherent population trapping (VSCPT) in two schemes for which there is a force which assists in the accumulation of atoms in the trapping state. In the first scheme, the F g =2 to F e =2 transition was studied where the existence of a semiclassical polarization gradient force even for a pure sigma + - sigma - configuration has been demonstrated which gives cooling for blue detuning. We also verify that cooling may be obtained for the F=2 to 1 and F=3 to 2 transitions; our fully quantum mechanical calculations yield a result which is consistent with recent experimental results of Valentin et al. (1992) but differ from previous semiclassical calculations. Secondly, we discuss a scheme of force-assisted VSCPT which combines VSCPT on the F g =1 to F e =1 transition with the coupling to another transition for which a strong sub-Doppler cooling force is present. This scheme allows velocity selective coherent population trapping and the polarization-gradient force to work under optimum conditions simultaneously. We find that both of these two schemes lead to efficient cooling of atoms.

Journal of Physics B Atomic Molecular and Optical Physics•Dec 28, 1995•3 citations
We show that an imperfection of velocity-selective coherent population trapping (VSCPT) in three-level atoms excited by standing light waves causes a rectified force on cooled atoms. The rectified force as well as the cooling force are calculated both analytically and numerically for and cascade three-level systems. Combination of these forces with the VSCPT mechanism can lead to localization of very cold atoms in potential wells created by the rectified force. This effect should be taken into account in experiments with VSCPT in standing waves, and can be used for realizing superlattices of cold atoms, in particular, cold Rydberg atoms.
We show that an ensemble of atoms in highly excited states with narrow center-of-mass momentum distribution (cold Rydberg atoms) can be obtained with velocity-selective (pi) - pulses and laser cooling by velocity-selective coherent population trapping (VSCPT). Both methods use three-level cascade systems with the uppermost state being the Rydberg one where the atoms are excited and cooled. Very high fraction of atoms can be cooled to subrecoil temperatures by the use of VSCPT in standing light waves.
ABSTRACT In this work we present an investigation of velocity-selective coherent population trapping (VSCPT) in asym- metric three-level schemes. The light force in such schemes is of an intrinsically transient character and shouldnot be described in a quasiclassical approach. Instead, results of the full quantum-mechanical calculations are presented with emphasis on their meaning to the efficiency of subrecoil laser cooling. 1 INTRODUCTION Laser cooling of neutral atoms has received significant advances by the introduction of velocity-selectivecoherent population trapping ((VSCPT) some years ago.1 Since it leads to atomic temperatures well below therecoil limit, studies of ultracold atoms and atomic interactions may be improved by magnitudes.The effect of VSCPT relies on optical pumping of atoms into a state WNC) which is a trap state for a certaincenter-of-mass velocity vO. This trap state is created by a destructive superposition of atomic states within amultilevel quantum system. Once being in such a state LWNC) the laser light does not interact anymore with theatom which leads to a decoupling with the rest of the system at vo. Atoms located outside this small velocityregion get a chance to be trapped by the momentum diffusion due to spontaneous emission of photons. Aftera sufficient long interaction time nearly all atoms are trapped inside a narrow momentum distribution whichcan be interpreted as cooling. The theoretical and experimental investigation of VSCPT is usually consideredby use of a three-level A-system as shown in Fig.1. Such a system can be found for example in a symmetrical
One-dimensional velocity-selective coherent population trapping (VSCPT) in a cascade atomic configuration, with the second excited level a Rydberg state, is investigated through numerical calculations. The trapping efficiency for the case of travelling wave lasers is derived from the solution of the optical Bloch equations. For excitation by bichromatic standing waves, the energy-band approach is applied. Although the cooling process is limited by the spontaneous emission decay of the Rydberg state, the coexistence of polarization-gradient cooling and VSCPT in the case of standing waves allows the preparation of the majority of the atomic population in a cold Rydberg state.
We have observed rectified dipole forces acting on three-level atoms in the cascade configuration. Laser cooled and trapped rubidium atoms are illuminated with an intense bichromatic standing wave (780 and 776 nm) tuned near resonance with the 5S1/2{\mathit{S}}_{1/2}S1/2​\ensuremath{\rightarrow}5P3/2{\mathit{P}}_{3/2}P3/2​\ensuremath{\rightarrow}5D5/2{\mathit{D}}_{5/2}D5/2​ transitions. The resulting rectified forces produce periodic potential wells (71-\ensuremath{\mu}m period), which localize the cold atoms. Experimental results are in reasonable agreement with theoretical predictions. These forces may be useful in atom optics and laser traps.
We present a fully quantum analysis of velocity selective coherent population trapping (VSCPT) in two schemes for which there is a force which assists in the accumulation of atoms in the trapping state. In the first scheme, the F g =2 to F e =2 transition was studied where the existence of a semiclassical polarization gradient force even for a pure sigma + - sigma - configuration has been demonstrated which gives cooling for blue detuning. We also verify that cooling may be obtained for the F=2 to 1 and F=3 to 2 transitions; our fully quantum mechanical calculations yield a result which is consistent with recent experimental results of Valentin et al. (1992) but differ from previous semiclassical calculations. Secondly, we discuss a scheme of force-assisted VSCPT which combines VSCPT on the F g =1 to F e =1 transition with the coupling to another transition for which a strong sub-Doppler cooling force is present. This scheme allows velocity selective coherent population trapping and the polarization-gradient force to work under optimum conditions simultaneously. We find that both of these two schemes lead to efficient cooling of atoms.