Anomalous polarization of the photoluminescence from anisotropic colloidal CdSe nanocrystals subject to external magnetic fields

We explain anomalous polarization of magnetophotoluminescence from CdSe nanocrystals with built-in anisotropy observed by Htoon et al., [Phys. Rev. Lett. 102, 017402 (2009)] in external magnetic fields up to 5 T. While there are two radiative doublets associated with the exciton ground state, it is the lower component of the upper doublet which demonstrates a truly anomalous behavior. We further describe complex behavior of the doublets components polarization in high-magnetic fields. The polarization degree of the upper component of each doublet varies with the applied magnetic field slower than that of the lower component. However, for the upper doublet this behavior is more pronounced and becomes apparent at much lower fields.