Fundamentals of Spin-Exchange Optical Pumping
نویسنده
چکیده
The standard model of Spin-Exchange Optical Pumping of He has come under close scrutiny as researchers try to maximize the quantity and polarization of He. This paper will review four important effects that have come to light: 1) pumping with frequency narrowed diode lasers significantly improves the polarization and production rate as compared to off-theshelf broadband sources 2) Rb-K mixtures again improve the production rate due to reduced collisional loss in K-He collisions, 3) a unexplained He wall relaxation mechanism that scales closely with alkali vapor pressure limits the attainable He polarization to about 80%, 4) a small collisionally-induced breakdown in the selection rules for optical pumping explains why narrowband lasers are so advantageous, and may explain some observed limitations for Rb-K pumping as well.
منابع مشابه
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