Abstract
We used continuous wave photoluminescence (cw-PL) and time-resolved photoluminescence (TR-PL) spectroscopy to compare the properties of magnetic polarons (MP) in two related spatially indirect II-VI epitaxially grown quantum dot systems. In the system the holes are confined in the nonmagnetic ZnTe quantum dots (QDs), and the electrons reside in the magnetic (Zn,Mn)Se matrix. On the other hand, in the system, the holes are confined in the magnetic (Zn,Mn)Te QDs, while the electrons remain in the surrounding nonmagnetic ZnSe matrix. The magnetic polaron formation energies in both systems were measured from the temporal redshift of the band-edge emission. The magnetic polaron exhibits distinct characteristics depending on the location of the Mn ions. In the system the magnetic polaron shows conventional behavior with decreasing with increasing temperature and increasing magnetic field . In contrast, in the system has unconventional dependence on temperature and magnetic field ; is weakly dependent on as well as on . We discuss a possible origin for such a striking difference in the MP properties in two closely related QD systems.
5 More- Received 15 January 2013
- Revised 3 April 2015
DOI:https://doi.org/10.1103/PhysRevB.92.035430
©2015 American Physical Society