Chapter 171 Itinerant electron metamagnetism of co sublattice in the lanthanide-cobalt intermetallics

Abstract

Publisher Summary This chapter discusses itinerant electron metamagnetism of Co sublattice in the lanthanide-cobalt intermetallics. The first-order transition (FOT) is observed in several lanthanide-cobalt (R-Co) intermetallics under the effect of varying external parameters and internal parameters. This transition occurs between a nonmagnetic or low-induced moment state and a ferromagnetic state. This phenomenon is called itinerant electron metamagnetism (IEM). The various models to describe IEM are discussed. At the beginning, the basic concepts of the band theory of metamagnetism describing the magnetically uniform states are presented. Then, the role of volume effects and spin fluctuation effects on the metamagnetic behavior are also briefly introduced. The magnetic properties of the systems consisting of both itinerant electrons and localized spins are formulated on the basis of the s-d model. The experimental overview of IEM is given. This section consists of three major parts. The role of the magnetic R-atom as well as the influence of the 3d electrons affecting the character of the magnetic phase transitions and the spin fluctuation scattering is discussed. High-field magnetization in the RCo 2 with one unstable magnetic sublattice is also discussed. IEM in the RCo 3 - and RCo 5 -based compounds is presented.