Fate of vacancy-induced supersolidity in 4He.
The supersolid state of matter, exhibiting nondissipative flow in solids, has been elusive for 35 years. The recent discovery of a nonclassical moment of inertia in solid 4He by Kim and Chan provided the first experimental evidence, although the interpretation in terms of supersolidity of the ideal crystal phase remains a subject to debate. Using quantum Monte Carlo methods we investigate the long-standing question of vacancy-induced superflow and find that vacancies in a 4He crystal phase separate instead of forming a supersolid. On the other hand, nonequilibrium vacancies relaxing on defects of polycrystalline samples could provide an explanation for the experimental observations.
Boninsegni
M
M
Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1, Canada.
Kuklov
A B
AB
Pollet
L
L
Prokof'ev
N V
NV
Svistunov
B V
BV
Troyer
M
M