Improvement of ultra-broadband near-infrared emission in Nd3+-Er3+-Pr3+ tri-doped tellurite glasses

Abstract Nd3+-Er3+-Pr3+ tri-doped tellurite glasses with lower phonon energy (766 cm−1) were prepared by conventional melt-quenching method. Under the excitation of 488 nm, an ultra-broadband emission from 1250 to 1650 nm with full-width at half-maximum (FWHM) of about 332 nm was found in Nd3+-Er3+-Pr3+ tri-doped tellurite glass, larger than that of recently reported tellurite glasses. The DSC curve showed that the prepared glass had a high glass transition temperature (Tg = 381 °C) and good crystallization resistance (ΔT = 195 °C). Raman spectra and XRD pattern revealed the information of different vibrational units and the amorphous structure of the prepared glass. The maximum absorption cross-section, emission cross-section and gain coefficient of the prepared tellurite glass were calculated as 1.05 × 10−20 cm2, 1.34 × 10−20 cm2 and 1.55 cm−1, respectively. Compared with the recently reported glasses, these values were improved. This indicates that better laser gain and fluorescence emission could be obtained in the prepared tellurite glass. The results showed that Nd3+-Er3+-Pr3+ tri-doped tellurite glass is a promising near-infrared optical material.