Energy transfer from rare‐earth element to Mn in (Ca,Sr)Ga 2 S 4 compounds

• Published in: Physica status solidi. A, Applications and materials science Applications and materials science, 2009-05, Vol.206 (5), p.1026-1029
• Main Authors: Obonai, Toshimitsu, Hidaka, Chiharu, Takizawa, Takeo
• Format: Article
• Language: English
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.200881190

For realizing a red‐colour emission using SrGa 2 S 4 compounds, Mn and rare‐earth‐element (REE) co‐doping is tried. Photoluminescence (PL) and photoluminescence excitation (PLE) spectra are measured using samples so prepared. As a result, enhancement of the Mn red emission is observed. Considering the 4f and 5d levels of REE in the host material, it is expected that the energy transfer from REE to Mn is caused by the weak coupling between the d levels of REE and Mn. Moreover, in the Ce co‐doping case, another process is expected as a resonant energy transfer between the 4f–5d transition of Ce 3+ and a certain transition of Mn 2+ . To specify the Mn 2+ levels related to the resonant transfer, PL spectra of a Mn only doped CaGa 2 S 4 single crystal and an undoped one are measured at low temperatures, though we could not find emission expected to be related to the resonant transfer. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)