Internal self-ordering in In(Sb,As), (In,Ga)Sb, and (Cd,Zn,Mn)Se nano-agglomerates/quantum dots

Nano-agglomerates of In(Sb,As) in InAs, (In,Ga)Sb in GaSb, and (Cd,Zn,Mn)Se in (Zn,Mn)Se are classified by transmission electron microscopy. In scanni ng transmission electron microscopy, atomic resolution Z-contrast images re veal different modes of internal compositional modulation on the atomic len gth scale, resulting for all three material systems in nano-agglomerates of an appropriate size that may constitute a new type of quantum dot. For oth er nano-agglomerates of In(Sb,As) in InAs and (In,Ga)Sb in GaSb, we observe d a second type of nanoscale ordering that results in nano-agglomerates wit h an internal compositional modulation on a length scale of a few nm. Both types of compositional modulation are discussed as having arisen from a rat her long-term structural response to a combination of internal and external strains. (C) 2001 American Institute of Physics.