Enhanced 2.7- and 2.9-μm emissions in Er 3+ /Ho 3+ doped fluoride glasses sensitized by Pr 3+ ions

Abstract In this report, Er3+/Ho3+/Pr3+ tri-doped fluoride glass was prepared. The enhancement of 2.7 and 2.9 μm emissions from Er3+/Ho3+doped system were achieved successfully after the addition of Pr3+. The combination of low OH− concentration, low maximum phonon energy and high mid-infrared transmittance is beneficial to the realization of mid-infrared emissions. The energy transfer mechanism among Er3+, Ho3+ and Pr3+ was investigated. The decay profiles of several levels were measured to further examine the enhanced mid-infrared emissions. Moreover, high stimulated emission cross sections at 2.7- and 2.9 μm (1.08 × 10−20 cm2 and 2.0 × 10−20 cm2, respectively) were determined. Er3+/Ho3+/Pr3+ tri-doped fluoride glass might provide a new choice for mid-infrared laser.