Vacancy distribution in a rotating solid ⁴ He

Abstract

Vacancy distribution is considered in a rotating solid 4 He immersed in a superfluid helium-II. Vacancies are considered as a quasiparticle gas of vacancions with a gap dispersion law. It is shown that the radial distribution depends on Poisson's ratio and practically not on Young's modulus. The treatment is based on a nonlinear theory unifying the elasticity theory equations and a Boltzmann-type transport equation valid for arbitrary angular velocities. The situation simulates, in a sense, the Kim and Chan rotational experiments where nonclassical inertia was observed. The model cannot be applied to solid 3 He. We do not presuppose in this work any supersolid fraction.

Effect of rotation on the elastic moduli of solid He4

“…V and VI. Pushkarov also claimed that the centrifugal force tends to change the distribution of defectons in the radial direction of a cylindrical solid 35 . It is essentially an ordinary phenomenon of centrifuge, and we find that it is negligibly small for rotation speed of the order of 1 rad/s, even compared to the effect of gravity on the vertical distribution of 3 He impuritons.…”

“…As mentioned in Sec. II, Pushkarov theoretically studied the effects of rotation on quantum properties of solid 4 He 2, 34,35 . He proposed a Fokker -Planck type equation for defectons in solid, and derived the temperature dependence of diffusion coefficient tensor in the temperature regime that phonon scattering deterimines the defecton diffusion.…”

“…Far before the 2004 Kim -Chan experiment, Pushkarov theoretically studied the effect of rotation on defecton quasiparticles, in which he focused on zero point vacancy in solid 4 He 2,34,35 . He discussed the motion of quasiparticles under sample rotation in terms of a Fokker -Planck equation, and found that quasiparticle diffusion is strongly suppressed in the direction perpendicular to the rotation axis 2,34 .…”