Electronic specific heats for amorphous and crystallized alloys

The low temperature specific heats of (Fe0.5Co0.5)72B20Si4Nb4 amorphous and crystallized alloys are measured and analyzed from 1.4 to 110 K. Specific heats can be well fitted by electronic and phonon contribution terms. It is found that the electronic contribution term in specific heat for amorphous alloy is larger than that for crystallized one, and this phenomenon has been interpreted in detail. The research shows that the electronic density of states at the Fermi level and the localized loose "rattler" atoms in oversized cage structure may make contributions to the enhancement of electronic specific heat coefficient γ, and result in a larger electronic contribution term. This study is significant for further understanding the structure-property relationship for amorphous alloys at low temperature.