Refractive index and birefringence measurements of the short-range order in the one-dimensional Heisenberg ferromagnet CsNiF3

Abstract

Magnetic short-range order in the one-dimensional Heisenberg ferromagnet CsNiF3 has been investigated by linear magnetic birefringence and optical phase retardation measurements The short-range order was found to extend beyond 120K. The contributions of out-of-plane fluctuations and of the interchain interaction have been recognised. The values of the photoelastic coefficients and of the lattice dilatations are also reported.