Research Publications in journals:
Structural and optical changes induced by incorporation of antimony into InAs/GaAs(001) quantum dots
Year:2010
Research Areas
Mechanical aeronautics and naval engineering
Information
Abstract
We present experimental evidence of Sb incorporation inside InAs/GaAs001 quantum dots exposed to an
antimony flux immediately before capping with GaAs. The Sb composition profile inside the nanostructures as
measured by cross-sectional scanning tunneling and electron transmission microscopies show two differentiated
regions within the quantum dots, with an Sb rich alloy at the tip of the quantum dots. Atomic force
microscopy and transmission electron microscopy micrographs show increased quantum-dot height with Sb
flux exposure. The evolution of the reflection high-energy electron-diffraction pattern suggests that the increased
height is due to changes in the quantum-dot capping process related to the presence of segregated Sb
atoms. These structural and compositional changes result in a shift of the room-temperature photoluminescence
emission from 1.26 to 1.36 m accompanied by an order of magnitude increase in the room-temperature
quantum-dot luminescence intensity.