Near Infrared Quantum Cutting Luminescence of Er3+/Tm3+ Ion Pairs in a Telluride Glass

The multiphoton near-infrared, quantum cutting luminescence in Er3+/Tm3+ co-doped telluride glass was studied. We found that the near-infrared 1800-nm luminescence intensity of (A) Er3+(8%) Tm3+(0.5%): telluride glass was approximately 4.4 to 19.5 times larger than that of (B) Tm3+(0.5%): telluride glass, and approximately 5.0 times larger than that of (C) Er3+(0.5%): telluride glass. Additionally, the infrared excitation spectra of the 1800 nm luminescence, as well as the visible excitation spectra of the 522 nm and 652 nm luminescence, of (A) Er3+(8%) Tm3+(0.5%): telluride glass are very similar to those of Er3+ ions in (C) Er3+(0.5%): telluride glass, with respect to the shapes of their excitation spectral waveforms and peak wavelengths. Moreover, we found that there is a strong spectral overlap and energy transfer between the infrared luminescence of Er3+ donor ions and the infrared absorption of Tm3+ acceptor ions. The efficiency of this energy transfer {I-4(13/2)(Er3+) -> I-4(15/2)(Er3+), H-3(6)(Tm3+) -> F-3(4)(Tm3+)} between the Er3+ and Tm3+ ions is approximately 69.8%. Therefore, we can conclude that the observed behaviour is an interesting multiphoton, near-infrared, quantum cutting luminescence phenomenon that occurs in novel Er3+-Tm3+ ion pairs. These findings are significant for the development of next-generation environmentally friendly germanium solar cells, and near-to-mid infrared (1.8-2.0 mu m) lasers pumped by GaN light emitting diodes.