Superfluidity of He-3 contained in aerogel

It is known that the critical temperature of superfluid He-3 confined withi n aerogel is suppressed, however, the exact nature of the superfluid phase is currently undetermined. We have designed an experiment in which the aero gel is surrounded by bulk superfluid of a known phase. Owing to the dipole- dipole interaction the bulk superfluid precesses at a frequency shifted fro m the Larmor frequency. The surface solid and the confined liquid component s of the He-3 inside the aerogel are in fast exchange and precess near the Larmor frequency. We have observed an additional NMR signal near the freque ncy of the bulk He-3 from the aerogel. (C) 2000 Elsevier Science B.V. All r ights reserved.