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Band gap and electronic structure of an epitaxial, semiconducting Cr0.80Al0.20 thin film
Z Boekelheide1, A X Gray, C Papp
1Department of Physics, University of California, Berkeley, Berkeley, California 94720, USA. zboekelheide@berkeley.edu
Abstract:
Cr(1-x)Al(x) exhibits semiconducting behavior for x = 0.15-0.26. This Letter uses hard x-ray photoemission spectroscopy and density functional theory to further understand the semiconducting behavior. Photoemission measurements of an epitaxial Cr(0.80)Al(0.20) thin film show several features in the valence band region, including a gap at the Fermi energy (E(F)) for which the valence band edge is 95 ± 14 meV below E(F). Theory agrees well with the valence band measurements, and shows an incomplete gap at E(F) due to the hole band at M shifting almost below E(F).
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