Visible quantum cutting through downconversion in green-emitting K2GdF5:Tb3+ phosphors.
- Resource Type
- Article
- Authors
- Lee, Te-Ju; Luo, Li-Yang; Diau, Eric Wei-Guang; Chen, Teng-Ming; Cheng, Bing-Ming; Tung, Chien-Yueh
- Source
- Applied Physics Letters. 9/25/2006, Vol. 89 Issue 13, p131121. 3p. 1 Diagram, 1 Chart, 3 Graphs.
- Subject
- *SYNCHROTRON radiation
*PHOSPHORS
*QUANTUM optics
*VACUUM ultraviolet spectroscopy
*PHOTON emission
- Language
- ISSN
- 0003-6951
Visible quantum cutting under excitations at 212 and 172 nm in a green-emitting phosphor K2GdF5:Tb3+ (11%) via a downconversion mechanism is investigated. The authors measured the vacuum ultraviolet (VUV) excitation and emission spectra and proposed mechanisms to rationalize the quantum-cutting effect. One short-UV or one VUV photon absorbed by Tb3+ is split into multiple visible photons emitted by Tb3+ through cross relaxation and direct energy transfer. Calculations indicate an optimal quantum efficiency as great as 189% for this phosphor. [ABSTRACT FROM AUTHOR]