The effect of reduced dimensionality on a semimetal: the electronic structure of the Bi(110) surface

We have studied the electronic structure of the semimetal surface Bi( 110) by high-resolution angle-resolved photoemission using synchrotron radiation. Several surface states are found very close to the Fermi level giving rise to a complex Fermi surface. As a consequence, the surface is a much better metal than the bulk, a fact which could help to explain the observation of superconductivity in granular systems built from small Bi clusters.