Ultra low density of CdTe quantum dots grown by MBE

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 confirm that both methods can be used for significant reduction of QDs density from 1010 QD/cm2 to 107–108 QD/cm2. For very low QDs density, identification of all QDs lines observed in the spectrum is possible.

► The methods of density control of CdTe quantum dots are presented.
► The impact of CdTe layer thickness and temperature is studied.
► Photoluminescence measurements confirm significant reduction of dots density.
► The low dots density allows identification of all lines in the spectrum.