Dissipation of quantum turbulence in the zero temperature limit

Abstract

Turbulence, produced by an impulsive spin down from angular velocity Ω to rest of a cube-shaped container, is investigated in superfluid He4 at temperatures 0.08 K-1.6 K. The density of quantized vortex lines L is measured by scattering negative ions. Homogeneous turbulence develops after time t≈20/Ω and decays as Lαt-3/2. The corresponding energy flux =ν′(κL)2αt-3 is characteristic of quasiclassical turbulence at high Re with a saturated energy-containing length. The effective kinematic viscosity in T=0 limit is ν′=0.003κ, where κ=10-3cm2s-1 is the circulation quantum. © 2007 The American Physical Society.