Nucleation and orientation of 4He crystals
نویسندگان
چکیده
2014 It is shown that liquid 4He can usually be overpressurized only 10-2 bars above the melting pressure. This value suggests that the nucleation takes place on the walls of the cell, not in the bulk liquid as calculated previously. Further theoretical effort on this problem is called for. In the presence of carefully degased graphite we confirm that the barrier to the nucleation disappears, and a method of obtaining macroscopic oriented single crystals is found. J. Physique LETTRES 41 (1980) L-283 L-285 15 JutN 1980,
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