Infinitely Many Commensurate Phases in a Simple Ising Model

Michael E. Fisher; Walter Selke

doi:10.1103/PhysRevLett.44.1502

Infinitely Many Commensurate Phases in a Simple Ising Model

Michael E. Fisher and Walter Selke

Phys. Rev. Lett. 44, 1502 – Published 9 June 1980; Erratum Phys. Rev. Lett. 45, 148 (1980)

Abstract

On the basis of systematic low-temperature expansions "to all orders", it is shown that an infinite sequence of spatially modulated commensurate phases, with wave vectors $\frac{π j}{(2 j + 1) a}$ ( $j = 0, 1, 2, \dots$ ), occurs in simple, anisotropic Ising models with nn couplings $J_{0}$ , $J_{1} > 0$ , in between spin-½ layers, and competing nnn interlayer couplings $J_{2} = - k J_{1}$ along one axis. The free energies, interfacial tensions, and phase boundaries are found for low $T$ in $d > 2$ dimensions.