Magneto-optics of excitons interacting with magnetic ions in CdSe/CdMnS colloidal nanoplatelets

Abstract: Excitons in diluted magnetic semiconductors represent excellent probes for studying the magnetic properties of these materials. Various magneto-optical effects, which depend sensitively on the exchange interaction of the excitons with the localized spins of the magnetic ions can be used for probing. Here, we study core/shell CdSe/(Cd,Mn)S colloidal nanoplatelets hosting diluted magnetic semiconductor layers. The inclusion of the magnetic Mn$^{2+}$ ions is evidenced by three magneto-optical techniques using high magnetic fields up to 15 T: polarized photoluminescence, optically detected magnetic resonance, and spin-flip Raman scattering. In particular, information on the Mn$^{2+}$ concentration in the CdS shell layers can be obtained from the spin-lattice relaxation dynamics of the Mn$^{2+}$ spin system.