Abstract
? 2022 Elsevier B.V.The intense 2.9 μm MIR (mid-infrared) luminescence corresponding to the Dy3+: 6H13/2→6H15/2 transition was achieved for the first time in Dy3+/Yb3+ ions co-doped SrF2 crystals. 2 at% Dy3+: SrF2，2 at% Dy3+/5 at% Yb3+: SrF2, and 5 at% Yb3+: SrF2 crystals were grown by Bridgman method. The influence of Yb3+ on its spectral properties and energy transfer mechanisms has been studied. In comparison to Dy3+ doped SrF2 crystals, Dy3+/Yb3+ co-doped crystals exhibit not only intense 2.9 μm emission but also longer high laser energy level lifetimes, favoring 2.9 μm population inversion and lasing behavior. Furthermore, the ET efficiency from Yb3+ to Dy3+ in Dy3+/Yb3+ co-doped crystals is found to be as high as 95.34%, indicating that the ET from Yb3+ is efficient. The results show that incorporating Yb3+ into Dy3+: SrF2 crystals improves the ability to achieve 2.9 μm lasing action, which could be used as a potential gain media for laser diode-pumped MIR lasers.
NSTL
Elsevier