ISSN - 00213640, EISSN - 10906487, JETP Letters, 1999, vol. 70, p. 550-555
Cs/GaAs(100) surface: Two-dimensional metal or Hubbard insulator?
The evolution of the characteristic electron energy loss spectra accompanying the deposition of cesium on GaAs(100) surfaces with various superstructural reconstructions is studied experimentally. It is shown that the appearance of loss peaks in the GaAs band gap for Cs cover-ages θCs>0.5 monolayers is due to resonances in the longitudinal and transverse polarizability of two-dimensional metallic clusters of adatoms. © 1999 American Institute of Physics.