Growth, spectral and 1.5–1.6 μm laser properties of Er:Yb:LuYSiO5 mixed crystal

Abstract

An Er:Yb:LuYSiO₅ crystal was grown by the Czochralski method, and its room-temperature polarized spectral properties were investigated. The crystal has a peak absorption cross-section of 2.38 × 10⁻²⁰ cm² at 979 nm and a peak emission cross-section of 1.06 × 10⁻²⁰ cm² at 1547 nm for E//Z polarization. The fluorescence lifetime of the ⁴I_13/2 multiplet of Er³⁺ is 6.48 ms and Yb³⁺→Er³⁺ energy transfer efficiency is 65 %. Because of the spectral inhomogeneous broadening caused by the combination of multiple cationic sites and mixed crystal structure, the full width at half maximum of the gain spectrum of the crystal is 27 nm for E//Z polarization at an inversion parameter of 0.5. Pumped by a 975.4 nm diode laser, a 1579 nm continuous-wave laser with a maximum output power of 95 mW and a slope efficiency of 11.7 %, as well as a multi-band tunable laser in 1546–1555, 1566–1574 and 1617–1620 nm were achieved in the crystal, respectively. The maximum output power of the tunable laser was 26 mW at 1554 nm.