Ultra low density of CdTe quantum dots grown by MBE

TL;DR

This paper demonstrates methods to significantly reduce the density of CdTe quantum dots grown by molecular beam epitaxy, enabling better control for applications requiring ultra-low QD densities.

Contribution

It introduces two effective approaches—raising deposition temperature and decreasing layer thickness—for controlling QD density during MBE growth.

Findings

QD density reduced from 10^10 to 10^7-10^8 QD/cm^2

Photoluminescence confirms all QD lines can be identified at very low densities

Methods enable precise control of QD density for advanced applications

Abstract

This work presents methods of controlling the density of self-assembled CdTe quantum dots (QDs) grown by molecular beam epitaxy. Two approaches are discussed: increasing the deposition temperature of CdTe and the reduction of CdTe layer thickness. Photoluminescence (PL) measurements at low temperature confirms that both methods can be used for significant reduction of QDs density from 10$^{10}$QD/cm$^2$ to 10$^7$-10$^8$QD/cm$^2$. For very low QDs density, identification of all QDs lines observed in the spectrum is possible.