Vortex-Free Landau State in Rotating Superfluid Helium

Abstract

Evidence is presented that below a rather large angular velocity, ${\ensuremath{\omega}}_{c1}$, there is a vortex-free state in rotating locked helium, which we call the Landau state. This is similar to the Meissner state in superconductors. We further show that all the properties of the rotating helium have counterparts in irreversible type-II superconductors and find that ${\ensuremath{\omega}}_{c2}$ (analogous to ${H}_{c2}$) greatly exceeds our high speeds of rotation.