Diode-pumped Double-pulsed Ho:Tm:LuLF Laser at 2.05 μm for CO_2 Differential Absorption Lidar (DIAL)

摘要

It has been realized that eye-safe 2-μm all-solid-state lasers are important laser sources for an accurate measurement of the CO_2 concentration in the atmosphere. Served as laser transmitters, they can be integrated into ground-based, airborne-base, and spaceborne-based CO_2 Differential Absorption Lidars (DIALs) to accomplish the measurement. In addition, the lasers are also ideal laser pumping sources for a ZnGeP_2 (ZGP) Optical Parametric Oscillator (OPO) or an Optical Parametric Amplifier (OPA) to achieve tunable laser output in 3～5 μm. In this spectrum region, the other important greenhouse gases, water vapor (H_2O), carbon monoxide (CO), and methane (CH_4) in the atmosphere can be measured. In this paper, we report a diode-pumped, double-pulsed, Q-switched, eye-safe Ho:Tm:LuLF laser at 2.05 μm developed for ground-based and airborne-based CO_2 Differential Absorption Lidars (DIALs). The technology can be easily transferred to a space-borne CO_2 DIAL in the future. The total output pulse energy of the laser is 220 m.T and 204 mJ per pair of pulses at 2 Hz and at 10 Hz respectively. The related optical energy conversion efficiency is 6.7% and 5.9% respectively.