Composition profiling at the atomic scale in III-V nanostructures by cross-sectional STM

Using cross-sectional STM we have studied the local composition in III/V nanostructures such as GaAs/InGaAs quantum wells, InGaNAs/InP quantum wells and quantum dots, and InAs/GaAs self-assembled quantum dots. We are able to determine the local composition by either simply counting the constituent atoms, measuring the local lattice constant or measuring the relaxation of the cleaved surface due to the elastic field of the buried strained nanostructures.