Li2O–Al2O3–ZnO–P2O5:Dy3+/Sm3+/Eu3+ glasses for solid-state yellow laser and color tunable phosphor applications

Laser and optical properties (absorbance, excitation/emission and decay time data) of Dy 3+ , Dy 3+ /Sm 3+ , Dy 3+ /Sm 3+ /Eu 3+ -doped Li 2 O–Al 2 O 3 –ZnO–P 2 O 5 glasses are investigated. Laser spectroscopic parameters of the dysprosium yellow emission show potentialities of the luminescent glass as yellow laser medium under excitation at 348 nm. The Dy 3+ /Sm 3+ -activated glass tonality can be shifted from neutral white of 4559 K under 350 nm excitation to yellowish-orange of 2033 K (85.3% color purity) upon 372 nm excitation. A shortening of the dysprosium 4 F 9/2 level lifetime revealed that Sm 3+ can be sensitized by Dy 3+ by means of a non-radiative energy transfer that could be occurring into Dy 3+ –Sm 3+ clusters with an efficiency of 0.13. The Dy 3+ /Sm 3+ /Eu 3+ -activated glass tonality can be shifted from warm white of 3387 K under 350 nm excitation to reddish-orange of 1638 K (92.1% color purity) upon 372 nm excitation. From lifetime data of the Dy 3+ ion 4 F 9/2 and Sm 3+ ion 4 G 5/2 levels is inferred that non-radiative energy transfers from dysprosium to europium and/or samarium and from samarium to europium could be occurring into Dy 3+ –Sm 3+ –Eu 3+ clusters with energy transfer efficiencies of 0.22 and 0.41, respectively.