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

Laser cooling of a metastable argon atomic beam

C. Ávila

Published Jul 26, 1996• 0 citations
Publisher

Abstract

A production of low velocity and monoenergetic atomic beams would increase the resolution in spectroscopic studies and many other experiments in atomic physics. Laser Cooling uses the radiation pressure to decelerate and cool atoms. The effusing from a glow discharge metastable argon atomic beam is affected by a counterpropagating laser light tuned to the cycling transition in argon. The Zeeman shift caused by a spatially varying magnetic field compensates for the changing Doppler shift that takes the atoms out of resonance as they decelerated. Deceleration and velocity bunching of atoms to a final velocity that depends on the detuning of the laser relative to a frequency of the transition have been observed. Time-of-Flight (TOF) spectroscopy is used to examine the velocity distribution of the cooled atomic beam. These TOF studies of the laser cooled atomic beam demonstrate the utility of laser deceleration for atomic-beam "velocity selection".

DOI
10.25148/etd.fi14032375

Related papers

Laser cooling and trapping of argon metastable atomic beam

Juan Carlos Catala

The high velocity of free atoms associated with the thermal motion, together with the velocity distribution of atoms has imposed the ultimate limitation on the precision of ultrahigh resolution spectroscopy. A sample consisting of low velocity atoms would provide a substantial improvement in spectroscopy resolution. To overcome the problem of thermal motion, atomic physicists have pursued two goals; first, the reduction of the thermal motion (cooling); and second, the confinement of the atoms by means of electromagnetic fields (trapping). Cooling carried sufficiently far, eliminates the motional problems, whereas trapping allows for long observation times. In this work the laser cooling and trapping of an argon atomic beam will be discussed. The experiments involve a time-of-flight spectroscopy on metastable argon atoms. Laser deceleration or cooling of atoms is achieved by counter propagating a photon against an atomic beam of metastable atoms. The solution to the Doppler shift problem is achieved using spatially varying magnetic field along the beam path to Zeeman shift the atomic resonance frequency so as to keep the atoms in resonance with a fixed frequency cooling laser. For trapping experiments a Magnetooptical trap (MOT) will be used. The MOT is formed by three pairs of counter-propagating laser beams with mutual opposite circular polarization and a frequency tuned slightly below the center of the atomic resonance and superimposed on a magnetic quadrupole field.

•Nov 21, 1998•0 citations

Laser Deceleration of an Atomic Beam

William D. Phillips, Harold J. Metcalf

Deceleration and velocity bunching of Na atoms in an atomic beam have been observed. The deceleration, caused by absorption of counterpropagating resonant laser light, amounts to 40% of the initial thermal velocity, corresponding to about 15 000 absorptions. Atoms were kept in resonance with the laser by using a spatially varying magnetic field to provide a changing Zeeman shift to compensate for the changing Doppler shift as the atoms decelerated.

Physical Review Letters•Mar 1, 1982•590 citations

Laser Cooling of a Helium Atomic Beam

Norio Morita, M. Kumakura

The laser cooling of a helium atomic beam in the 2s3S1 metastable state has been demonstrated. Using a single-mode LNA (La1-x Nd x MgAl11O19) laser resonant with the 2s3S1-2p3P2 transition, the metastable atoms are cooled by the Doppler cooling method combined with the Zeeman-tuning technique. To monitor the velocity distribution, the Doppler profile of the 2p3P2-3d3D3 transition is observed. As a result, the most probable velocity of the metastable helium atoms, which is initially 750 m/s, is decelerated to 90 m/s.

Japanese Journal of Applied Physics•Sep 1, 1991•8 citations

White light cooling of an atomic beam

Miao Zhu, Chris W. Oates, J. L. Hall

To compensate the Doppler shift in the laser cooling process, two methods were developed:frequency chirping,1 which tunes the laser frequency rapidly, and a spatially varying magnetic field,2 which tunes The atomic energy level. An alternative approach is to use laser light with a continuous spectrum (white light).3,4 Using only a counterpropagating white-light beam will decelerate the atoms in the beam, hut it will not yield a large velocity compression.4,5 To achieve significant cooling, Hoffnagle5 proposed the use of an additional single-frequency laser beam, copropagating with the atomic beam, to counterbalance the nonresonant scattering force from the Lorentzian tail of the atomic transition.

Quantum Electronics and Laser Science Conference•May 12, 1991•0 citations

Van der Waals - Zeeman transitions of slow metastable argon atoms Ar*(3P2)

M. Hamamda, Thierry Taillandier-Loize, F. Perales +4 more

Metastable argon atoms Ar*(3P2), produced by electron bombardment of a nozzle beam of ground state Ar atoms, are slowed down from their initial thermal velocity of 560 m/s down to a few tens of m/s, using a standard Zeeman slower. In this decelerator, a repulsive force is induced by a counter-propagating σ+- polarized laser beam, locked in frequency on the3P2-3D3closed transition (λ= 811.5 nm) and then detuned by 340 MHz. A special profile of longitudinal magnetic field is adjusted in order to maintain atoms in resonance with light all over the device, by compensating the variable Doppler shift by the convenient Zeeman shift. Low velocities, e.g. 55 m/s, are accessible but due to spontaneous emission randomly distributed recoil momentums enlarge both angular and velocity distributions of the beam. Nevertheless, by placing off axis collimating slits and grating, it is in principle possible to observe transmission and/or diffraction phenomena specific of low velocities.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•May 1, 2011•0 citations

Transverse laser cooling of a metastable argon beam: Dependence on the interaction time

Michael Drewsen, Nikolay V. Vitanov, Harold K. Haugen

A pulsed metastable argon beam is transversely cooled in one dimension via the closed 4s[11/2${]}_{2}^{\mathit{o}\mathrm{\ensuremath{-}}}$4p[21/2${]}_{3}$ transition. A standing light wave, orthogonal to the atomic beam and located just at the source, provides the cooling. In all the measurements, the maximum electric field is equivalent to a Rabi frequency of \ensuremath{\sim}220 natural linewidths. The enhancement of the metastable atom flux is measured as a function of the interaction time with a time-of-flight technique. The dependence on the laser detuning is investigated and compared with theory.

Physical Review A•Apr 1, 1993•6 citations
A production of low velocity and monoenergetic atomic beams would increase the resolution in spectroscopic studies and many other experiments in atomic physics. Laser Cooling uses the radiation pressure to decelerate and cool atoms. The effusing from a glow discharge metastable argon atomic beam is affected by a counterpropagating laser light tuned to the cycling transition in argon. The Zeeman shift caused by a spatially varying magnetic field compensates for the changing Doppler shift that takes the atoms out of resonance as they decelerated. Deceleration and velocity bunching of atoms to a final velocity that depends on the detuning of the laser relative to a frequency of the transition have been observed. Time-of-Flight (TOF) spectroscopy is used to examine the velocity distribution of the cooled atomic beam. These TOF studies of the laser cooled atomic beam demonstrate the utility of laser deceleration for atomic-beam "velocity selection".
The high velocity of free atoms associated with the thermal motion, together with the velocity distribution of atoms has imposed the ultimate limitation on the precision of ultrahigh resolution spectroscopy. A sample consisting of low velocity atoms would provide a substantial improvement in spectroscopy resolution. To overcome the problem of thermal motion, atomic physicists have pursued two goals; first, the reduction of the thermal motion (cooling); and second, the confinement of the atoms by means of electromagnetic fields (trapping). Cooling carried sufficiently far, eliminates the motional problems, whereas trapping allows for long observation times. In this work the laser cooling and trapping of an argon atomic beam will be discussed. The experiments involve a time-of-flight spectroscopy on metastable argon atoms. Laser deceleration or cooling of atoms is achieved by counter propagating a photon against an atomic beam of metastable atoms. The solution to the Doppler shift problem is achieved using spatially varying magnetic field along the beam path to Zeeman shift the atomic resonance frequency so as to keep the atoms in resonance with a fixed frequency cooling laser. For trapping experiments a Magnetooptical trap (MOT) will be used. The MOT is formed by three pairs of counter-propagating laser beams with mutual opposite circular polarization and a frequency tuned slightly below the center of the atomic resonance and superimposed on a magnetic quadrupole field.
The laser cooling of a helium atomic beam in the 2s3S1 metastable state has been demonstrated. Using a single-mode LNA (La1-x Nd x MgAl11O19) laser resonant with the 2s3S1-2p3P2 transition, the metastable atoms are cooled by the Doppler cooling method combined with the Zeeman-tuning technique. To monitor the velocity distribution, the Doppler profile of the 2p3P2-3d3D3 transition is observed. As a result, the most probable velocity of the metastable helium atoms, which is initially 750 m/s, is decelerated to 90 m/s.
To compensate the Doppler shift in the laser cooling process, two methods were developed:frequency chirping,1 which tunes the laser frequency rapidly, and a spatially varying magnetic field,2 which tunes The atomic energy level. An alternative approach is to use laser light with a continuous spectrum (white light).3,4 Using only a counterpropagating white-light beam will decelerate the atoms in the beam, hut it will not yield a large velocity compression.4,5 To achieve significant cooling, Hoffnagle5 proposed the use of an additional single-frequency laser beam, copropagating with the atomic beam, to counterbalance the nonresonant scattering force from the Lorentzian tail of the atomic transition.
Metastable argon atoms Ar*(3P2), produced by electron bombardment of a nozzle beam of ground state Ar atoms, are slowed down from their initial thermal velocity of 560 m/s down to a few tens of m/s, using a standard Zeeman slower. In this decelerator, a repulsive force is induced by a counter-propagating σ+- polarized laser beam, locked in frequency on the3P2-3D3closed transition (λ= 811.5 nm) and then detuned by 340 MHz. A special profile of longitudinal magnetic field is adjusted in order to maintain atoms in resonance with light all over the device, by compensating the variable Doppler shift by the convenient Zeeman shift. Low velocities, e.g. 55 m/s, are accessible but due to spontaneous emission randomly distributed recoil momentums enlarge both angular and velocity distributions of the beam. Nevertheless, by placing off axis collimating slits and grating, it is in principle possible to observe transmission and/or diffraction phenomena specific of low velocities.
A pulsed metastable argon beam is transversely cooled in one dimension via the closed 4s[11/2${]}_{2}^{\mathit{o}\mathrm{\ensuremath{-}}}4p[21/24p[21/24p[21/2{]}_{3}$ transition. A standing light wave, orthogonal to the atomic beam and located just at the source, provides the cooling. In all the measurements, the maximum electric field is equivalent to a Rabi frequency of \ensuremath{\sim}220 natural linewidths. The enhancement of the metastable atom flux is measured as a function of the interaction time with a time-of-flight technique. The dependence on the laser detuning is investigated and compared with theory.