Emission properties of 1.8 and 2.3 μm in Tm3+-doped fluoride glass

Аннотация

In this work a Tm³⁺-doped fluoride glass with good thermal stability is prepared. Intensive 1.8 and 2.3 μm emissions are obtained when pumped by an 800 nm laser diode. And the 1.48 μm emission is limited because of the much strong radiation around 1.8 μm. On the basis of absorption spectrum, radiative properties are investigated and discussed according to Judd–Ofelt parameters (Ω₂, Ω₄, Ω₆) calculated by Judd–Ofelt theory. Besides, absorption and emission cross-sections of ³F₄ → ³H₆ transition are figured out and analyzed by using McCumber and Beer–Lambert theories. The high gain around 1.8 μm was predicted by the large σ_emiτ_rad product (29.8 × 10^–21 cm² ms). The results obtained indicate that the Tm³⁺-doped fluoride glass can be a promising 2.0 μm laser glass material.