Dimple instability in a metastable superfluid film

It is shown that the surface dimple in a metastable rotating superfluid film becomes unstable as the surface spinodal of the thick film is approached. The dimple ceases to exist when its free energy E _d equals the excess free energy E _c of a critical hole in the film, which indicates the breakdown of the metastable film. The lifetime of the metastable film upon approach of the instability is calculated. Possibilities of enhancing the instability are briefly addressed.