Experimental Evidence for a Structure-Induced Minimum of the Density of States at the Fermi Energy in Amorphous Alloys

Abstract

First photoemission spectra are reported for the valence bands and core levels of quench-condensed ${\mathrm{Au}}_x{\mathrm{Sn}}_{100-x}$ ($0<~x<~100$) films in the amorphous and the crystalline state. It is found that (1) the valence-band spectra for the $20<~x<~80$ region, measured just after condensation, exhibit a decrease in intensity towards the Fermi energy $E_{\mathrm{F}}$ which can be understood in terms of a minimum in the density of states near $E_{\mathrm{F}}$ and (2) the minimum near $E_{\mathrm{F}}$ is most pronounced at an alloy concentration where the highest stability for the amorphous phase has been found.