NMR Characterization of Phase Separation in Highly Polarized He-3 - He-4 Solutions above 450 mK
Résumé
Laser optical pumping techniques have been successfully applied to concentrated He-3-He-4 gaseous mixtures. Using a He-3 cryostat, these mixtures were subsequently liquefied and studied down to 450 mK, using pulsed NMR techniques. Observation of highly nuclear polarized solutions and of phase separation (demixion) in the mixtures is reported. Measurements of magnetic relaxation times and the dynamics of coexisting phases in this system are discussed.