Pulsed NMR experiments in superfluid 3He confined in aerogel

Pulsed NMR experiments have been performed in both B and supercooled A phases of superfluid He-3 in aerogel. Dependencies of spin precession frequency on tipping angle in B-phase of superfluid He-3 in aerogel are found to be different for pure He-3 and for the cell preplated with He-4. A sharp increase of the frequency for tipping angles greater than 104degrees was observed in low temperature superfluid phase of He-3 in He-4 preplated aerogel as it is expected for the B-phase structure of the order. parameter. Dependencies of the frequency on the tipping angle in supercooled A-phase are similar for both pure He-3 and He-4 preplated aerogel. (C) 2003 Elsevier Science B.V. All rights reserved.