Bosonic Lasing of Collective Exciton Magnetic Polarons in CuCl2-Doped CdS Nanoribbons: Implications for Quantum Light Sources

Diluted magnetic semiconductor (DMS) is an important system for realizing room-temperature(RT) ferromagnetism(FM). In DMS, the exchange interactions between the spins of the carrier or exciton and spins of magnetic ions are the cause of the magnetic polaron effect by the self-trapping of the carriers or excitons, leading to the formation of small ferromagnetic domains, and their collective behaviors were expected for long though many difficulties have been come across. Spin-polarized excitons coupled with LO phonons could form exciton magnetic polarons(EMP) in a micrometer-sized DMS structure. Here, we studied CuCl2-doped CdS nanoribbons(NRs), synthesized by chemical vapor deposition(CVD) method, in which the EMP formation was identified and a single mode lasing from collective EMPs under femtosecond laser pump was observed at room temperature, similar to an exciton-polariton condensation binding by spontaneous magnetic moment. Such behavior happened due to the dynamic scattering of exciton condensate by ...