The anisotropy and field dependence of the Neel temperature in pseudo-one-dimensional antiferromagnetic systems

Abstract

Using a double-time temperature-dependent Green function, an expression for TN as a function of eta (the ratio of the interchain in the intrachain exchange interaction), the uniaxial anisotropy (K) and the external magnetic field (H) is obtained which explains the observed behaviour of the Neel temperature in some pseudo-one-dimensional antiferromagnetic systems. The effect of anisotropy on the perpendicular susceptibility is also examined. The effect of a field on the Neel temperature is discussed for two cases-for an external magnetic field applied (i) parallel and (ii) perpendicular to the easy axis.