BISMUTH-INDUCED ELECTRONIC STATES AT (2X1)-BI/III-V(110) INTERFACES

An investigation and a comparison of the Bi-induced electronic states at the (2 X 1)-Bi/InSb(110) and (2 X 1)Bi/GaSb(110) interfaces is presented. The electronic transitions between Bi-induced states have been studied by high-resolution electron energy loss spectroscopy: a huge absorption structure is found at 0.48 eV in the stable (2 X 1) reconstructed phase for the Bi/InSb(110) interface, and at 0.55 eV for the (2 X 1)-Bi/GaSb(110) interface. This feature distinguishes an interband electronic transition between Bi-induced filled and empty electronic states, for both (2 X 1)-symmetry interfaces. Moreover, the Bi-induced occupied states are detected in the valence band for both systems, by ultra-violet photoemission spectroscopy.