Enhanced 2.7- and 2.84-µm emissions from diode-pumped Ho³âº/Er³âº-doped fluoride glass.

ABSTRACT

This work reports the intense emissions at 2.7 and 2.84 µm in a Ho³âº/Er³âº-codoped fluoride glass (ZrF4-BaF2-YF3-AlF3). An extensive transmission spectrum and the absence of strong OH⁻ absorption guarantee the observation of mid-infrared (IR) emissions. For the Ho³âº/Er³âº-codoped sample, the 2.7- and 2.84-µm emissions are 5.8 and 3.8 times higher with larger emission cross-sections (10.2×10⁻²¹ and 9.8×10⁻²¹ cm²), respectively. Meanwhile, other near to middle infrared emissions (1200, 2045 nm emissions from Ho³âº and 980, and 1535 nm emissions from Er³âº ions) are all enhanced. The collective enhanced effect originates from the disappearance of nonradiative decay processes after codping Er³âº and Ho³âº ions. Hence, the advantageous spectroscopic characteristics of Ho³âº/Er³âº-codoped ZBYA glass indicate that this kind of fluoride glass may be an attractive host to develop solid-state lasers for 3 µm.