1. Temperature and pressure behavior of the emission bands from Mn-, Cu-, and Eu-doped ZnS nanocrystals
- Author
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Kun Ding, B. S. Ma, F. H. Su, Z. L. Fang, Guohui Li, and Shijie Xu
- Subjects
Materials science ,Photoluminescence ,business.industry ,Doping ,Hydrostatic pressure ,Analytical chemistry ,Wide-bandgap semiconductor ,General Physics and Astronomy ,chemistry.chemical_element ,Atmospheric temperature range ,Ion ,chemistry ,Crystal field theory ,Optoelectronics ,business ,Europium - Abstract
The temperature and pressure dependence of the photoluminescence from ZnS:Mn2+, ZnS:Cu2+, and ZnS:Eu2+ nanocrystals were investigated in the temperature range from 10 to 300 K and under hydrostatic pressure up to 6 GPa at room temperature. The orange emission (590 nm) from the 4T1-6A1 transition of Mn2+ ions, the green emission (518 nm) from the 4f65d1-4f7 transition of Eu2+ ions and the blue emission (460 nm) related to the transition from the conduction band of ZnS to the t2 level of Cu2+ ions were observed in the Mn-, Eu-, and Cu-doped samples, respectively. It was found that all of these emission bands decrease in intensity with increasing temperature. Among them the intensity of the Mn-orange emission dropped faster. The activation energies were estimated to be 58, 16, and 42 meV for the Mn-orange, Eu-green, and Cu-blue emissions, respectively. A negative pressure coefficient of −26 meV/GPa was obtained for the Mn-orange emission, which agrees with the value calculated from the crystal field theory. ...
- Published
- 2004