Superiority quantitation of laser-driving in Sm3+ doped germanium tellurite glass phosphors as bio-friendly lighting sources

Abstract

Intense multi-peak red fluorescence of Sm3+ has been quantitatively characterized and the superiority of laser pumping has been verified in heavy metal germanium tellurite (HGT) glasses. The dipole-dipole interaction between Sm3+-Sm3+ ions is proved to be a dominant mechanism governing the non-radiative energy transfer. The net emission power and the net emission photon number in HGT-Sm-1.0 glass are increased by 393.61 μW and 13.26 × 1014 cps under the excitation of the 464 nm laser compared with those of the 470 nm LED pumping, and the corresponding quantum yield is as high as 17.55% which is 60% higher than that in the common LED. The environmental-friendly red emissions (590–780 nm) occupy a ratio of up to 83.3% in total released photon numbers, and the maximum luminous flux of Sm3+ reaches to 0.16 lm, exhibiting the availability of employed laser-driving approach. Moreover, the high-quality red light can be further optimized by narrow-band filter, which can intercept the residual laser fully compared with broad-band exciting sources. Efficient red fluorescence emissions and large absolute spectral parameters confirm the superiority of laser-driving on Sm3+ doped HGT glass phosphors for lighting source, which further promotes the development of bio-friendly illumination sources.