Abstract
Emission, excitation and reflection spectra at various temperatures are studied. Under the C -band excitation, a simple emission band independent of the activator concentrations is observed for all the Ca(S: Se): Sn 2+ phosphors. As the fraction of CaSe is increased, the band-peak (545 mµ for CaS: Sn 2+ at 77 K) shifts constantly towards shorter wavelengths and finally reaches 518 mµ in CaSe: Sn 2+ at 77K. In the excitation spectra, the curves characteristic of the Tl + -type ion center in the O h crystal field can be obtained for all the Ca(S: Se): Sn 2+ phosphors. The peaks of the C , B and A excitation bands are found at 311, 332 and 364 mµ for CaS: Sn 2+ , and at 327, 344 and 373 mµ for CaSe: Sn 2+ at 77 K. For all the Ca(S: Se): Sn 2+ phosphors, two additional excitation bands (409 and 448 mµ for CaSe: Sn at 77 K) are observed in the longer wavelength region of the A band at low temperatures.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
