NMR Study of Solid 3He Droplets In Phase-Separated 3He-4He Mixtures

We report measurements on solid3He droplets embedded in a solid4He matrix. A feature of our experiments is that the mixture crystals, of 1%3He concentration, are grown under constant pressure conditions to minimise the formation of defects. Upon cooling the mixture isotopic phase separation is clearly observed in both pressure and NMR data. At a pressure of 36 bar the3He separates as solid droplets. NMR measurements on these droplets indicate values of T1and T2similar to those in bulk solid3He at the same pressure in the temperature-independent régime. Measurements of the bounded diffusion in the droplets indicate a spin diffusion coefficient similar to that in bulk solid3He at the same pressure. These measurements also show the size of the droplets to be a few microns.