Evidence for a Spin Emulsion

Magnetic small-angle neutron scattering from the itinerant electron magnet, Y(Mn1-xFex)2, in which ferromagnetic and antiferromagnetic spin correlations compete, is found to follow an anomalous Q-6 dependence (Q=4sin/). It is suggested that this scattering is the magnetic analogue of that predicted for a structural microemulsion by Teubner's extension of conventional Kirste-Porod scattering to well-defined interfaces with extreme differences between mean and Gaussian curvatures. The “spin-emulsion-like” morphology of magnetic interfaces in Y(Mn1-xFex)2 is confirmed both qualitatively and quantitatively by a simple model based upon reported near neighbor Mn and Fe spin correlations