1.
Nanotechnology
; 19(43): 435710, 2008 Oct 29.
Article
in English
| MEDLINE
| ID: mdl-21832714
ABSTRACT
InAs quantum dots embedded in InGaAs quantum well (DWELL: dots-in-the-well) structures grown on nanopatterned GaAs pyramids and planar GaAs(001) surface are comparatively investigated. Photoluminescence (PL) measurements demonstrate that the DWELL structure grown on the GaAs pyramids exhibits a broad quantum well PL band (full width at half-maximum â¼ 90 meV) and a higher quantum dot emission efficiency than the DWELL structure grown on the planar GaAs(001) substrate. These properties are attributed to the InGaAs quantum well with distributed thickness profile on the faceted GaAs pyramids, which introduces a tapered energy band structure and enhances carrier capture into the quantum dots.