Interaction of a beam of metastable argon atoms and a diode laser beam

Dominik Schneble

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.

Hidetoshi Katori, Fujio Shimizu

The laser cooling and trapping of argon and krypton isotopes in the 1s5 metastable state are demonstrated using stabilized diode lasers. Even isotopes of krypton are separately trapped by tuning the laser frequency. For Ar and 84Kr, approximately 6×105 and 1×105 atoms are trapped, respectively.

C. Ávila

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".

C. J. Joachain