Estimation of the lateral dimensions of epitaxial submonolayer CdSe/ZnSe quantum dots

• Published in: Nanotechnology Vol. 31; no. 28; p. 285001
• Main Authors: Basilio-Ortiz, J C, Sutara, F, Hernández-Calderón, I
• Format: Journal Article
• Language: English
• Published: England IOP Publishing 24.04.2020
• Subjects: CdSe quantum dots; epitaxial quantum dots; fractional monolayer quantum dots; quantum dots size; submonolayer quantum dots; ultra-thin quantum dots
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/1361-6528/ab83b5

CdSe fractional monolayer quantum dots (FMQDs) embedded in a ZnSe matrix were produced by atomic layer epitaxy with a nominal coverage of 0.5 monolayer. They have a thickness of a/2, where a is the strained perpendicular lattice constant of cubic CdSe. Their photoluminescence spectra at low temperature exhibit narrow and intense excitonic emission around 2.759 eV. Based on the experimental excitonic emission energy and applying the factorized-envelope approximation, we have estimated that the lateral dimensions of these FMQDs are around 4-5 nm and their density is ∼3×1012 cm−2.