Magnetic contributions to the low-temperature specific heat of Sc79Fe21 nanoglass

The specific heat (Cp) of the Sc79Fe21 nanoglass and Sc75Fe25 melt-spun ribbons was measured in zero and non-zero applied magnetic fields for a temperature range of 1.9 to 7 K. The plots for the Cp/T-vs-T2 without an applied magnetic field show an “upturn” at lower temperatures. Based on the variations of the “upturn” with applied magnetic fields and the magnetism of the alloys, the “upturn” was attributed to the effect of the ferromagnetic clusters. The calculated number of ferromagnetic clusters within the Sc79Fe21 nanoglass was much smaller than that within the Sc75Fe25 melt-spun ribbon, most likely because of the chemically heterogeneous structure of the nanoglass.