Electronic and magnetic properties of amorphous and crystallineZr40Cu60−xFexalloys

摘要: Electronic states and localized magnetic moments their interactions were studied in amorphous crystalline ${\mathrm{Zr}}_{40}{\mathrm{Cu}}_{60\ensuremath{-}x}{\mathrm{Fe}}_{x}$ alloys for $0\ensuremath{\le}x\ensuremath{\le}12$. Electrical resistivity, susceptibility, high-field magnetization measurements performed. In the dilute Curie-Weiss behavior is seen susceptibility associated with (${\ensuremath{\mu}}_{\mathrm{eff}}\ensuremath{\approx}3{\ensuremath{\mu}}_{B}$) on iron atoms. At higher concentrations ferromagnetism observed. also of ($0lx\ensuremath{\le}6$) alloys; however, these dependence Fe concentration appears complex effective atoms are very small (${\ensuremath{\mu}}_{\mathrm{eff}}\ensuremath{\approx}0.7{\ensuremath{\mu}}_{B}$). There some evidence that local environment important may depend sensitively quench rate used making samples or, perhaps, room-temperature ageing effects samples. The exhibit a negative $\frac{d\ensuremath{\rho}}{dT}$ from 1.4 to 300 K. This not be Kondo spin-flip scattering but it consistent several other mechanisms including localized-spin-fluctuation scattering, $s$-$d$ nonmagnetic model, tunneling alloy, or quasi-liquidmetal-pseudopotential scattering. A recent theory due Nagel Tauc nearly-free-electron approach metallic glass shown this last idea account features exhibited by Zr-Cu system. concentrated ($xg6$) alloys, resistance maxima hysteresis at low temperatures. For $x=12$ random ferromagnetic state develops ${T}_{0}=30$ K, which five times smaller than ${T}_{0}$ corresponding alloy. saturation moment alloy considerably case. similar systems crystalline-to-amorphous transition greatly weakens magnetism.