Electronic structure of thin epitaxial Be films on Si(111)

We show that single crystal films of Be can be grown on Si(111) substrates, exhibiting nearly identical surface electronic bandstructure to that found on the pristine Be(0001) surface of bulk Be. Segregation of silicon atoms into the film causes strong doping of the surface states. For sufficiently thin films, the quality and uniformity are sufficient to observe well-defined quantum well states. In addition to making single-crystal beryllium more accessible for future studies, thin film growth of beryllium on high-resistivity silicon substrates may open up new possibilities to investigate earlier suggestions of surface superconductivity.