Very thin films ofHe3: A new phase

Abstract

We report the first measurements of the superfluid density of thin ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ films for a broad range of thicknesses. In contrast to previous experiments, we find good agreement with the predictions of the general theory for the suppression of the superfluid transition temperature ${\mathit{T}}_{\mathit{c}}$. In addition, we find evidence for a new phase of the superfluid in films thinner than 2750 Å.