Anomalous Properties around Magnetic Instability in Heavy Electron Systems

Abstract

Spin fluctuations in heavy electron systems around their antiferromagnetic instability are discussed from a phenomenological point of view by using a sum rule for the dynamical susceptibility valid in the strong correlation limit. As a result the dynamical susceptibility takes the same form as in the standard spin fluctuation theory of weak itinerant antiferromagnetism, although the values for the parameters are substantially different from those in d-metals. The expression for the Néel temperature given in terms of the staggered magnetization at 0 K and the spin fluctuation parameters are successfully compared with experiment. Anomalous (non-Fermi liquid) behaviors reported for the specific heat and electrical resistivity in some heavy electron systems around their magnetic instabilities are explained in terms of this theory.