Carrier-mediated magnetism and bound magnetopolarons in quantum dots

While Mn-doped quantum dots (QDs) offer versatile control of magnetic order [1], important challenges remain in understanding of these systems beyond the mean-field approximation. Furthermore, to describe the carrier-mediated magnetism in arrays of magnetic QDs and their non-equilibrium properties, it is important to consider the presence of both electrons and holes in these systems. We develop a formalism that accounts for both equilibrium and light-controlled magnetopolaron effects [2]. We study QDs of different sizes and find that their magnetic and photo-induced properties are extremely size-sensitive. We compare our theory with recent experiments on circularly-polarized photoluminescence in magnetic QDs [3] where both the magnetopolaron energies and power dependence of the circular polarization were measured. We thank I. R. Sellers for valuable discussions. Supported by ONR and NSF-ECCS CAREER. [1] L. Besombes et al., Phys. Rev. Lett. 93, 207403 (2004); R. M. Abolfath, A. G. Petukhov, and I. Zutic, Phys. Rev. Lett. 101, 207202 (2008). [2] T. Dietl and J. Spalek, Phys. Rev. Lett. 48, 355 (1982). [3] I. R. Sellers et al., unpublished.