Hydrogen Spin Exchange and Radiation Trapping in AN Optically Pumped Alkali Vapor.

F. A. Franz

F. A. Franz

Ben A. Olsen, Brian Patton, Yuan‐Yu Jau +1 more

Will Happer, E. Miron, R. J. Knize +1 more

We have discussed in detail how spin exchange collisions can transfer momentum from an alkali vapor, which can be easily polarized by optical pumping. For hydrogen atoms the spin exchange rates can be very fast and the alkali vapor can be only a small trace contamination of the atomic hydrogen gas. (AIP)

D. Tupa, L. W. Anderson

Calculations are presented on the effect of radiation trapping on the electron-spin polarization that can be produced by optical pumping of an alkali-metal vapor in a weak magnetic field. Radiation trapping severely limits the polarization that can be obtained in a weak magnetic field.

S. G. Redsun, R. J. Knize, G. D. Cates +1 more

We have produced highly spin-polarized atomic hydrogen by spin-exchange optical pumping. A tunable ring dye laser is used to polarize rubidium atoms by optical pumping. The cell containing the rubidium vapor is coated with paraffin in order to reduce spin relaxation due to wall collisions. Hydrogen gas is dissociated in an inductive discharge and flows continuously through the cell, in which the hydrogen atoms are polarized by spin-exchange collisions with the polarized rubidium atoms. Atomic-hydrogen polarization as high as 2〈${\mathit{J}}_{\mathit{z}}$${\mathrm{〉}}_{\mathrm{H}}$=0.72(6) has been observed, which is the highest polarization yet produced by this method. However, the rubidium polarization may be limited to this value due to radiation trapping at higher rubidium densities. The spin-relaxation rate of atomic hydrogen on a paraffin-coated cell is also measured and corresponds to about 7600 wall bounces between wall relaxation.