POLARIZATION STUDY OF THE P(1X1)-PHASES AND P(1X2)-PHASES OF BI GASB(110) USING LINEARLY POLARIZED SYNCHROTRON-RADIATION/

The polarization dependence of the surface state bands of the ordered p(1 X 1)- and p(1 X 2)-phases of Bi/GaSb(110) at monolayer coverages h as been studied with the technique of angle-resolved ultraviolet photo emission spectroscopy. Four new Bi-induced surface state bands (S', S' ', S''', and S(IV)) have been observed. The polarization dependence of these states have been probed at the high symmetry points of the surf ace Brillouin zone and compared with the polarization dependence of co rresponding surface state bands of other group-V semimetals on III-V(1 10) compound semiconductors. For the (1 X 1)-phase, the states S'', S' '', and S(IV) all exhibited p(z)-like dependence at all of the high sy mmetry points. The polarization dependence of S' was observed to evolv e from p(xy)-like at the XBAR' point of the surface Brillouin zone to p(z)-like character at the other high symmetry points. The polarizatio n dependence of S'', S''', and S(IV) were relatively unaffected by the phase transition of the overlayer from the (1 X 1)-phase to the (1 x 2)-phase.