Green Tb3+:ZBLAN fiber laser

We demonstrate continuous-wave laser operation of a terbium (Tb 3+ )-doped ZBLAN fiber emitting in the green spectral region. Under pumping at 486 nm, laser oscillation at 542 nm was achieved in a 4 m long Tb 3+ :ZBLAN double-clad fiber. A maximum output power of 6.2 mW was obtained with a slope efficiency of 1.2% with respect to the launched pump power and 4.1% not taking into account the transmitted pump light. Versus the actual absorbed pump power, the efficiency is estimated to be comparable to crystalline fluoride hosts. The results represent a significant improvement over previously reported Tb 3 ⁺-doped fiber lasers and highlight the potential of fluoride fibers for compact visible laser sources provided sufficient absorption efficiency can be achieved.