Small ordered magnetic moment in a weak itinerant electron ferromagnet Sc3In

We performed neutron diffraction study of Sc-In alloy which indicates that the ordered magnetic moment in this material is intrinsically tiny. This tiny magnetic moment (0.04-0.05 μB/Sc) is not caused by the uncompensated antiferromagnetic ordering of large magnetic moments. The temperature dependence of the resistivity is in proportion to T32, which suggests that this material is naturally close to the quantum critical point where ferromagnetism vanishes. This is consistent with the fact that this material shows ferromagnetism in an extremely narrow range of compositions which is typical of materials exhibiting quantum critical phenomenon. In the vicinity of the Curie temperature the magnetization depends on magnetic fields as M5∝μ0H. This behavior for itinerant ferromagnets can be explained by assuming that the total spin fluctuation amplitude is conserved.