Magnetic structure of γ-Fe precipitates in a Cu matrix

The recent discovery of a periodic distortion of the lattice structure of gamma -Fe precipitates in Cu motivated the authors to re-examine the magnetic structure of these precipitates using a neutron diffraction technique. They find that the spin structure is that of a longitudinal type-1 antiferromagnet as is well known but the spins are within a c plane and modulated in space with a wavevector Q which is the same as that of the displacement wave of the lattice. Several features of the spin structure are discussed.