The two Laves phase compounds ZrZn2 and NbFe2 belong to the small group of low temperature itinerant magnets. While ZrZn2 shows a ferromagnetic (FM) transition with a small ordered moment, Nb 1-yFe2+y exhibits a magnetically ordered ground state which is believed to be of spin-density-wave type for |y| < 0.015 and FM for y ≥ 0.02. Furthermore, signatures of a logarithmic Fermi-liquid breakdown suggest the existence of a quantum critical point on the Nb-rich side at y ≈ -0.015. In both systems a largely enhanced Stoner factor indicates the presence of FM correlations, which, in general, support the observability of a conduction electron spin resonance (ESR). We present our results of ESR measurements on high quality ZrZn2 single crystals and on polycrystalline samples of Nb 1-yFe2+y. The ESR data of both compounds is analysed in terms of a conduction ESR being subject to strong exchange enhancement effects.
ASJC Scopus subject areas
- Physics and Astronomy(all)