Phase Transitions in Two-Dimensional SuperfluidHe3

Abstract

A discussion of phase transitions in two-dimensional ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ is presented. A new type of phase transition is proposed, in which "islands of reversed $\overrightarrow{\mathrm{l}}$" spontaneously nucleate, leading to an Ising-like transition. It is shown that such transitions may need to be taken into account, possibly competing with the well-know Kosterlitz-Thouless transition. Consequences of both types of transition are discussed.