Crystal Growth, Property Investigation, and the Deactivation Effect of Tb3+ in Dy3+/Tb3+ Codoped LiYF4 Crystals: Promising Crystals for All-Solid-State Yellow Lasers
We report the growth, thermal characteristics, and spectroscopic properties of Dy3+-doped (Dy:YLF) and Dy3+/Tb3+ codoped LiYF4 (Dy,Tb:YLF) crystals. The yellow emission at ∼575 nm of the Dy3+:4F9/2 → 6H13/2 transition of the Dy,Tb:YLF crystal was enhanced by the deactivation effects of codoped Tb3+ ions. The corresponding ET efficiency from the Dy3+:6H13/2 to Tb3+:7F4 level was as high as 55.4%, which greatly reduced the energy level lifetime of 6H13/2, and an emission at 575 nm with the emission cross section σem = 4.58 × 10–21 cm2 was obtained, confirming the effective deactivation of Tb3+ ions, which is beneficial to resolve the self-termination bottleneck effect and achieve enhanced yellow laser emission. Hence, the Dy,Tb:YLF crystal is an attractive and potential laser medium for LD-pumped all-solid-state yellow lasers.