title: Hybrid spin-exchange optical pumping of 3He.
abstract: We demonstrate spin-exchange optical pumping of 3He using a "hybrid" K-Rb vapor mixture. The Rb atoms absorb light from a standard laser at 795 nm, then collisionally polarize the potassium atoms. Spin-exchange collisions of K and 3He atoms then transfer the angular momentum to the 3He with much greater efficiency than Rb-3He. For a K-rich vapor, the efficiency of the hybrid spin-exchange collisions approaches 1/4, an order of magnitude greater than achieved by pure Rb pumping. We present the first measurements of actual photon efficiencies (polarized nuclei produced per absorbed photon), and show that a new parasitic absorption process limits the total efficiencies for both hybrid and pure Rb pumping.
authors.affiliation: Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: Earl
authors.initials: E
authors.lastname: Babcock
authors.forename: Ian
authors.initials: I
authors.lastname: Nelson
authors.forename: Steve
authors.initials: S
authors.lastname: Kadlecek
authors.forename: Bastiaan
authors.initials: B
authors.lastname: Driehuys
authors.forename: L W
authors.initials: LW
authors.lastname: Anderson
authors.forename: F W
authors.initials: FW
authors.lastname: Hersman
authors.forename: Thad G
authors.initials: TG
authors.lastname: Walker