ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Spin-wave excitations have been studied by neutron inelastic scattering in a series of amorphous (FexCr1−x)75P15C10 alloys with x=0.75, 0.725, and 0.700 and are correlated with small-angle neutron scattering (SANS) results. The Curie temperatures of the three compositions are 212, 181, and 134 K, respectively. These alloys show reentrant spin-glass behavior characterized by a maximum in the spin stiffness parameter D below 0.5 Tc, and an increase in the spin-wave linewidth at low T. This corresponds to the development of a static spin-glass phase as observed by the onset of a Lorentzian-squared component in the SANS. The maximum in D shifts to higher values of T/Tc for smaller Fe concentrations reflecting the increased width of the exchange field distribution. The results for the T dependence of the spin stiffness parameter and the subcritical SANS are remarkably similar to those for crystalline FeCr alloys1 having the same Tc, although the Fe concentration in the analogous crystalline materials is much lower (e.g., Tc=178 K) for crystalline Fe26Cr74 and close to the expected percolation concentration.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.340532
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