Abstract
Nuclear magnetic susceptibility and Zeeman-exchange relaxation time TZX of solid 3He have been measured by pulsed NMR method using Pomeranchuk cooling technique between 15 mK and 0.97 mK in a static field of about 70 gauss. Magnetic transition to the antiferromagnetic phase was observed at 1.00 mK where the susceptibility decreased to 42% of its maximum value. This drop in susceptibility coincides with the abrupt leveling of 3He pressure in cooling process which shows thermodynamically a phase transition due to abrupt decrease of solid 3He entropy.
The magnitude of TZX is consistent with the one estimated from BPP (Bloembergen-Purcell-Pound) theory, but the observed temperature dependence can not be explained on this basis.
