Electronic heat capacity of the rare-earth metals

Abstract

The mass enhancement of the conduction electrons due to their interaction with the ionic magnetic moments is derived. The effect of the mass enhancement on the specific heat is considered as a function of temperature in both the paramagnetic and the spin-polarized ferromagnetic cases. The experimental magnitude and the field dependence of the low-temperature specific heat of Pr metal clearly indicates large mass enhancement. An estimate shows that the theory gives a good account of these observations. A comparison between the result of band-structure calculations and the experimental electronic heat capacity indicates that the electronic masses in the magnetically ordered heavy rare-earth metals are enhanced due to the spin waves. This indication is found to be fairly consistent with a theoretical estimate of the effect.