Coherent Effects in Optically Pumped Hydrogen - Gas.

N. Skribanowitz

Thomas J. Mcilrath

Nicolai G. Basov, Vladilen S Letokhov

Sheng Li, Jingbiao Chen, Hong Mei Guo

A model is presented to investigate the effects of quenching gas on atomic polarization in optically pumped atomic vapor cell. For Rb atomic vapor cell, the formula obtained by the present model can well describe the relation between the atomic polarization and the pressure of quenching gas nitrogen or hydrogen, and shows that if we keep the pumping rate and the quenching gas pressure unchanged, the atomic polarization tends to be one definite value as the atomic density increases. In addition, the fitting values of the pumping rate show certain dependance on radiation trapping and a model is presented to investigate it.

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)

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.