Magnetic susceptibility of (formula presented) alloys

This paper provides theoretical results for the magnetic susceptibility in the single (S), double (D), and triple (T) spin-density wave (SDW) states of (Formula presented) alloys. Whereas the S SDW state is collinear, the D and T SDW states are noncollinear phases which are stabilized at higher impurity concentrations. As expected, the susceptibility along any spin direction is suppressed below the Néel temperature. Averaged over all possible domains, the magnetic susceptibility of each SDW phase approaches the same limit near the Néel temperature. At low temperatures, however, the average susceptibility depends on the relative sizes of the electron and hole Fermi surfaces. For Fermi surfaces of approximately the same size, the average susceptibility is largest in the S SDW state and smallest in the T SDW state. But when one Fermi surface is sufficiently larger than the other, the relative magnitudes of the average susceptibilities are reversed. As a consequence, the transition between different SDW phases with temperature or doping concentration should be marked by a sudden change in the magnetic susceptibility.