Fig. 4: Relation between magnetization and CPL polarization in Mn:PEPI and proposed interaction mechanism.
a Superposition of PL polarization and magnetization curve of Mn:PEPI at 4 K and Brillouin function for a non-interacting J = 5/2 spin system. b Schematic of proposed interaction between excitons and manganese spins in an external magnetic field. XB and XD denote bright and dark exciton, respectively. ΓXF is the exciton formation rate, N the occupancy of the state, σ the polarization of emission, ΓD is the dark exciton emission rate depending on the magnetic field strength B and the manganese magnetization MMn. Superscript and subscript + /− denote the corresponding spin state. (i) A magnetization-dependent exciton formation rate favors the occupation of a specific spin state. (ii) Dark exciton spin states are occupied equally, but the manganese induces a spin-dependent recombination pathway leading to different radiative rates.
