Bi-induced electronic states at the interface with n- and p-type GaAs(110)

The electronic transitions of ordered Bi nlonolayers grown at room lemperature on n- and p-type doped GaAs(110) were studied by high-resolution electron energy loss spectroscopy. The absorption edge of the semiconducting Bi monolayer was measured and a band gap of 0.05 eV is eslimated, A new absorption feature is shown, parlicularly evident on p-doped GaAs and its origin can be related to states generated by the dangling and broken bond acceptor-like states located at the regular dislocation arrays in the Bi overlayer.