Universal linear relation between the critical field and the inverse susceptibility for Co-based Laves-phase metamagnets

Magnetizations and the temperature dependence of susceptibility for several kinds of Co-based Laves-phase metamagnets have been investigated. A universal linear relation between the critical field of the metamagnetic transition, BC, and the inverse of susceptibility-maximum, χ(Tmax)−1, was demonstrated. The root-mean amplitude of spin fluctuations at the susceptibility-maximum temperature,ξp(Tmax), was estimated to be about 0.4μB/Co from the BC–χ(Tmax)−1 relation on the basis of the spin fluctuation theory for itinerant-electron metamagnets.