Multicolor emission tuning in Yb3+/Tm3+/Er3+ triply doped germanate-tellurite glasses

Vera-Saravia L.C.; Quispe-Aquice J.C.; C G.L.; Marega E., Jr.; Rivera V.A.G.; Ramirez J.V. · Journal of Non-Crystalline Solids (2026) · DOI: 10.1016/j.jnoncrysol.2026.124302

Resumen

Luminescent materials capable of producing tunable visible emission have attracted considerable attention due to their potential applications in solid-state lighting, lasers, multicolor displays, and advanced photonic devices. In this context, here we evaluated the structural and optical properties of tri-doped germanate-tellurite glasses fabricated via the melt-quenching method. Transparent, homogeneous, and structurally stable glasses were produced, which were analyzed using techniques including Fourier transform infrared spectroscopy (FTIR), density measurements, X-ray diffraction (XRD), optical absorption spectroscopy, excitation spectroscopy, luminescence and up-conversion. Under 980 nm laser excitation, tunable multicolor emission—controlled by varying the Er3+ and Tm3+ concentrations—was achieved through up-conversion and energy transfer processes involving Yb3+ sensitization and subsequent excitation of Er3+ and Tm3+ ions, yielding a combination of red, green, and blue light. Warm light emission was observed at low excitation power and gradually shifted toward a greenish hue as the excitation power increased from 20 to 180 mW. Glasses containing 0.5 mol% Er3+ and 0.3 or 0.6 mol% Tm3+ exhibited a trend toward the yellow-green region rather than perfect white light. This indicates that while a low total rare-earth content combined with a high Tm3+/Er3+ allows for a clearer harmony among the red, green, and blue bands, the green emission ultimately dominates. In contrast, at higher Er3+ concentrations (1.0 and 1.5 mol%), quenching effects were observed, which disrupted this harmony and significantly suppressed the intensity of the blue light emission. The results confirmed that the samples exhibit adjustable optical properties, making them suitable for applications in the photonics field as materials for the development of tunable light sources.

Instituciones: Universidad Nacional de San Agustín de Arequipa