OPTICAL ANISOTROPIES IN STRAINED SI SIGE SYSTEMS/

Optical anisotropies were studied in two types of Si/Ge systems: strai n-adjusted superlattices, and thin Ge quantum wells on Si. For the sup erlattices, investigations of the polarization dependence showed that the topmost valence band is of heavy-hole character. For the Ge monola yer quantum wells, the optical transitions were identified as a no-pho non transition and a TO-replica. Furthermore, the symmetry of the inte rmediate state over which the transitions take place at the zone-cente r was identified.