Excitonic magnetic polarons and their luminescence in II-VI diluted magnetic semiconductor micro-nanostructures

Abstract

Spin is an intrinsic nature of the angular momentum of elementary particle like electron and photon. Currently the collective spin behaviors of the multi-electrons in condensed matter, such as GMR, CMR and topological insulator which are the behaviors of ground state, have been a research focus in the condensed matter physics, due to the fact that the collective spin is related to electronic transports. Exciton is another type of bosonic quasiparticle, an excited state of electronhole pair in solid, which has a short lifetime and can recombine to emit light. Whether excitons can also exhibit the spin-polarized dominance before they recombine, has not been understood yet. It is proposed that excitons form condensate by themselves or light binding. Can coupled spins conduce to the formation of the exciton condensate in solid? Excitonic magnetic polaron (EMP) is the composite exciton of ferromagnetically coupled spins and free excitons in magnetic semiconductors, which may lead to ferromagnetic Bose-Einstein condensate (BEC) due to the binding of collective spins in a microstructure, like the photon binding excitons (exciton polaritons) in an optical cavity However, this subject has not been a research focus yet. Here in this paper, we review the progress of the EMP formation, its dynamic behaviors and spin polarized collective EMP emission and lasing in Ⅱ-VI dilute magnetic semiconductor micro-structures in our group Besides, we also present some expectations for the applications or advances in the quantum phenomena such as spin-related emission and lasing, spin induced BEC, photon induced magnetism and Hall effect, etc. Even more achievements of EMP could be expected in the future.