title: Self-organized formation of GaSb/GaAs quantum rings.
abstract: Ring-shaped GaSb/GaAs quantum dots, grown by molecular beam epitaxy, were studied using cross-sectional scanning tunneling microscopy. These quantum rings have an outer shape of a truncated pyramid with baselengths around 15 nm and heights of about 2 nm but are characterized by a clear central opening extending over about 40% of the outer baselength. They form spontaneously during the growth and subsequent continuous capping of GaSb/GaAs quantum dots due to the large strain and substantial As-for-Sb exchange reactions leading to strong Sb segregation.
authors.affiliation: Institut für Festkörperphysik, Technische Universität Berlin, 10623 Berlin, Germany. timm@physik.tu-berlin.de
authors.forename: R
authors.initials: R
authors.lastname: Timm
authors.forename: H
authors.initials: H
authors.lastname: Eisele
authors.forename: A
authors.initials: A
authors.lastname: Lenz
authors.forename: L
authors.initials: L
authors.lastname: Ivanova
authors.forename: G
authors.initials: G
authors.lastname: Balakrishnan
authors.forename: D L
authors.initials: DL
authors.lastname: Huffaker
authors.forename: M
authors.initials: M
authors.lastname: Dähne