Ising model with antiferromagnetic next-nearest-neighbor coupling. IV. Relative magnetic scattering intensity and anomalous scattering

Publisher Website
Google Scholar
Abstract
When antiferromagnetic next-nearest-neighbor interactions are introduced into an Ising model, anomalous scattering can occur on certain lattice systems, in the sense that isotherms of the reciprocal scattering intensity versus the square of the wave number can acquire (in theory) negative initial slopes at sufficiently high temperatures. Scattering from cubic lattices has only normal Ornstein-Zernike form for small wave number. The general dependence of the scattering on wave vector across the Brillouin zone is investigated at high temperatures, where it may be expresses as (direction-dependent) truncated Fourier series. The anomalous scattering from two exactly soluble one-dimensional models is analyzed, and the possibility of actually detecting anomalous scattering from one-dimensional magnetic systems is raised.