Spectroscopic properties of Er:Lu2O3 crystal in mid-infrared emission

High optical quality Er3+ doped Lu2O3 single crystal with optimum doping concentration was grown by Floating zone (Fz) method. The spectral properties and Judd-Ofelt (JO) analysis were reported. The emission cross-section at 2772 nm was calculated to be 2.47 × 10−20 cm2 with FWHM of 188 nm. The fluorescence lifetime of 4I11/2 and 4I13/2 energy level was fitted to be 1.62 ms and 4.02 ms. Optimum lifetime ratio (τlow/τup) is beneficial to laser operation. Compared with reported Er3+ doped crystal, the larger spectral quality factors Q and low inversion ratio P of 7 at.% Er:Lu2O3 crystal indicate that it has a favorable laser performance for 2.8 μm laser operation.