We have performed an angle-resolved photoemission investigation, using synchrotron radiation, of the surface electronic structure of Be(0001). At normal emission we observe a surface state in the 3+-4- band gap with a binding energy of 2.80.1 eV. Away from it disperses parabolically towards EF with an effective mass of m*/m1.5. For Latin small letter h with stroke<40 eV, the energy dependence of the photoexcitation cross section for this state shows rapid variations caused by changes in the local electromagnetic field at the surface. For Latin small letter h with stroke>40 eV, it shows only weak structure. This high-energy behavior is quite different from the large resonances observed for surface states on other metals and is associated with the short penetration depth of the Be surface state. The dispersion of this state is measured along M» and » in the two-dimensional surface Brillouin zone. For a small range of k around M», there is evidence for two surface states in the M2 - M4- gap with binding energies of 1.80.1 eV and 3.00.1 eV.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics