Artículos de revistas
Zero-point divacancy concentration in the shadow wave function model for solid He-4
Registro en:
Physical Review B. Amer Physical Soc, v. 80, n. 17, 2009.
1098-0121
WOS:000272310400007
10.1103/PhysRevB.80.172302
Autor
Pessoa, R
de Koning, M
Vitiello, SA
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) We address the issue of interaction between zero-point vacancies in solid He-4 as described within the shadow wave function model. Applying the reversible-work method and taking into account finite-size effects, we obtain a zero-point monovacancy concentration of (2.03 +/- 0.02)x10(-3), which is slightly higher than the result due to Reatto for the same model. Utilizing the same methodology, we then consider the divacancy, taking into account both the in-plane as well as out-of-plane configurations with respect to the basal plane. We find no significant anisotropy between both conformations. Furthermore, although there is a small binding tendency, the expected divacancy concentration is only similar to 4-5 times larger than the value expected in the absence of any clustering propensity, 2.5x10(-5). This result suggests that, within the employed model description, no vacancy aggregation leading to phase separation is to be expected in the ground state. 80 17 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)