Spectroscopic and luminescent properties of Yb,Er:LaSc3(BO3)4 crystals

Abstract Absorption and luminescence spectra and luminescence kinetics of Yb have been measured in crystals of Yb,Er:LaSc3(BO3)4 (LSB) for a wide region of variation of activator concentration. It has been established that an effective absorption cross-section of Yb3+ at the maximum of 982 nm is equal to 1.16 × 10−20 cm2. Effective absorption and emission cross-sections of Er3+ at generation wavelength of 1555 nm are equal to σ ab =4.4×10 −21 and σ em =5.2×10 −21 cm −2 , respectively. 2 F 5/2 Yb 3+ → 4 I 11/2 Er 3+ energy transfer for dominating luminescence centers in Yb,Er:LSB is described satisfactorily by a dipole–dipole interaction with C DA =4.16×10 −39 cm −6 . Yb–Yb energy migration is very efficient and described by a hopping mechanism with C DD =3.5×10 −38 cm −6 , the quantum efficiency in Yb0.15 (6.7 × 1020 cm−3), Er0.015 (6.7 × 1019 cm−3):LSB crystals has achieved 98%. Investigations of Yb,Er:LSB crystals have shown them to have necessary combination of properties to get an effective generation of 1.5 μm eye-safe radiation with laser diode pumping.