Magnetic field influence on optical properties of Cd1−xMnxS (x = 0; 0.3) quantum dots: Photoluminescence study

We have synthesized CdS and Cd0.7Mn0.3S nanocrystals with diameters of about 4.5 nm. These materials have been studied using photoluminescence spectroscopy with various excitation energies in the temperature range from 1.8 to 300 K, in magnetic field up to 5T. We registered surface and defect states as well as two Mn2+ energy levels that correspond to Mn2+ ions in two different crystal environments. We proposed the scheme of energy levels and transitions that explain obtained experimental results.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Photoluminescence spectra of CdS and Cd0.7Mn0.3S nanocrystals are presented. ► Magnetic field up to 5T at 1.8 K was applied. ► Surface, defect states and two Mn2+ levels are registered. ► Mn2+ ions registerd in two different crystal environments. ► MnS phases are registered in the surfaces of the sample.