Magnetic field effects on the diffuse scattering of a spin-frustrated spinel ferrite ZnFe2O4 single crystal

Magnetic diffuse scattering of ZnFe2O4 originated from the spin-frustration on the network of the corner sharing tetrahedra has been studied under magnetic fields up to 7 T by neutron scattering. The previous work indicated that the characteristic diffuse scattering distributed in the (HK0) zone of this compound can be well explained with the assumptions that the nearest-neighbor interaction is ferromagnetic and the third-neighbor interaction is antiferromagnetic. In the present experiments it is found that the fields up to 7 T dramatically decrease the spherical diffuse scattering around the (4 0 0) Bragg point. The features of the field dependence of the diffuse scattering around this (4 0 0) point and that along the zone boundary passing through the (3 0 0) point are shown. Strangely enough, the ferromagnetic correlations in ZnFe2O4 are weakened rather than strengthened in the magnetic field