title: Fate of vacancy-induced supersolidity in 4He.
abstract: 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.
authors.affiliation: Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Boninsegni
authors.forename: A B
authors.initials: AB
authors.lastname: Kuklov
authors.forename: L
authors.initials: L
authors.lastname: Pollet
authors.forename: N V
authors.initials: NV
authors.lastname: Prokof'ev
authors.forename: B V
authors.initials: BV
authors.lastname: Svistunov
authors.forename: M
authors.initials: M
authors.lastname: Troyer