Comments on the evidence for sharp and gradual optical absorption edges in amorphous germanium

Abstract

AbstractSeveral investigators have analyzed optical data on amorphous Ge films prepared by evaporation on room‐temperature substrates to derive a sharp absorption edge near 0.5 eV. A re‐examination of their work shows that the sharp edges, found hitherto, may be artifacts resulting from either experimental or calculational errors and that the preponderance of the current evidence favors a gradual absorption edge.