Mean-field theory calculations of the spin-flop phase transition in orthorhombic antiferromagnets

Publisher Website
Google Scholar
Abstract
The introduction of a small amount of orthorhombic anisotropy into a uniaxial antiferromagnet results in an extension of the region of coexistence of spin-flopped and antiferromagnetic phases along a hyperbola in the hard-easy plane. Mean-field theory calculations on the orthorhombic system show that the thickness of the extension decreases very rapidly beyond the edge of the uniaxial spin-flop asteroid unless the orthorhombic energy is large. It is also found that for small values of the orthorhombic anisotropy energy three different phases (one antiferromagnetic and two spin flopped) may coexist for certain applied fields.