Electron spin resonance in the Heusler alloy YbRh2Pb

Abstract

An electron spin resonance (ESR) signal was observed in a concentrated Kondo lattice, Heusler alloy YbRh2Pb. It is attributed to the combined effect of the 4f local magnetic moments of Yb3+ and conduction electrons. It is shown that the significant broadening and disappearance of the ESR line at temperatures above 20 K is caused by the processes of the spin-lattice relaxation of the Yb3+ ions through the first excited Stark doublet with an activation energy Δ ≈ 73.5 K. A comparison of the ESR data for YbRh2Pb and some other undoped intermetallic compounds based on ytterbium, cerium, and europium indicates that hybridized electronic states occurring as the result of hybridization between the localized 4f electrons and the collectivized conduction electrons constitute a fundamentally new source of ESR. © Pleiades Publishing, Ltd., 2009.