Anisotropic antiferromagnet

Fig. 33. Plot of isothermal magnetization and differential susceptibility of a weakly anisotropic antiferromagnet versus the applied external field (Ms = saturation magnetization of a sublattice)...

Fig. 34. Theoretical magnetic phase diagram of a weakly anisotropic antiferromagnet...

The field dependence of magnetization and of the susceptibility of a weakly anisotropic antiferromagnet - according to the molecular field theory - is described in Fig. 33 and the H = f(T) diagram in Fig. 34. 

The thermal conductivity of CeCoIns has been studied in a magnetic field rotating within the 2D planes (Izawa et al., 2001). These data clearly reveal fourfold symmetiy for the thermal conductivity and indicate that the symmetiy most likely belongs to dx -y implying that the anisotropic antiferromagnetic fluctuation is relevant to the superconductivity. Independent... 

Temperature dependence of magnetic susceptibility of the PF6 salt was measured from 300 to 4 K at 5 T [35], The spin susceptibility of this salt gradually decreases from 300 to 50 K. Below 50 K, the susceptibility exhibits a rapid decrease accompanied by anisotropic temperature dependence, which is an indication of the long-range antiferromagnetic ordering. A one-dimensional Heisenberg model is... 

In antiferromagnets, the neighboring spins are aligned antiparallel, there is no net macroscopic moment in zero applied field, and the susceptibility is anisotropic below the Neel temperature, TN. Most antiferromagnets are insulating solids (NiO and MnO, for example). 

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