In this work, BaCl2:Eu2+,S2- is employed as model system to investigate the formation and tunable evolution of localized excitonic magnetic polarons (LEMPs) in Eu-S codoped divalent metal halides, in which Eu-S bonding in BaCl2 with Eu2+ 5d-f hybridization markedly enhances the band edge emission, shifting from 401 to 412 nm with rising EuS content, and the absorption band edge shifts from 3.02 to 2.85 eV, with EMP character. Moreover, EuS doped in different hosts (Ba n > 1), demonstrating the LEMP-cooperative radiative processes. This study establishes rare-earth-sulfur codoped halides as a promising materials platform for tuning luminescence through coupled spin-lattice-exciton interactions.
huang et al. (Mon,) studied this question.