%0 Journal Article %J Physical Review B %D 1997 %T Enhancement of surface NMR by laser-polarized noble gases %A Room, T. %A Appelt, S. %A Seydoux, R. %A Hahn, E. L. %A Pines, A. %K he-3 %X

The transfer of spin polarization from laser-polarized helium and xenon to spins such as H-1 and C-13 On the surface of high-surface-area solids (Aerosil) is demonstrated over a temperature range from 4 to 200 K. The transfer mechanism is dipole-dipole cross relaxation between the spins of the adsorbed mobile noble gas and the surface spins (spin-polarization-induced nuclear Overhauser effect). The enhancement of surface proton magnetization by laser-polarized helium at 4 K and 10 K is between one and twofold. Using laser-polarized xenon, enhancement factors of up to 20 were obtained when compared to the Boltzmann polarization in a field of 4.2 T and at a temperature of 130 K.

%B Physical Review B %V 55 %P 11604-11610 %8 May 1 %@ 0163-1829 %G English %U ://WOS:A1997WY50400096 %N 17 %M WOS:A1997WY50400096 %! Enhancement of surface NMR by laser-polarized noble gases %R Doi 10.1103/Physrevb.55.11604