Enhancement of upconversion intensity in Er3+ doped tellurite glass in presence of Yb3+

Applied Physics B (Impact Factor: 1.78). 104(1):233-236. DOI: 10.1007/s00340-011-4422-6

ABSTRACT TeO2–PbO glasses doped/codoped with Er3+/Er3+-Yb3+ ions have been fabricated by melting and quenching method. Efficient frequency upconversion emissions spanning from blue
to red regions corresponding to the 2H11/2, 4S3/2→4I15/2 and 4F9/2→4I15/2 transitions, respectively, upon excitation with 976 nm diode laser radiation have been observed. The variations observed
in the intensity of whole upconversion emission spectra due to the presence of the Yb3+ ions are reported and discussed in detail.

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