Nd:LuAP laser at 1083 nm for atmospheric helium LiDAR

Doppler LiDAR at 1083 nm enables remote sensing of metastable helium in the highest atmospheric layers beyond 250 km altitude. Realizing efficient laser sources at this wavelength remains challenging for conventional Nd 3+ -doped gain media, whose emission typically peaks near 1064 nm. Here, we revisit the perovskite-structure crystal Nd 3+ :LuAlO 3 (Nd:LuAP), which exhibits its main emission peak at 1083 nm. Various Nd:LuAP crystals were grown by the Czochralski method, resolving some ambiguity in the phase diagrams previously proposed and yielding an effective Nd 3+ segregation coefficient of ∼0.5. We determined the absorption cross-sections in the pump wavelength range between 790 nm and 813 nm, revised the Stark level splitting, and found a peak emission cross-section of 3.2 × 10 −19 cm 2 at 1083 nm and an order of magnitude lower values around 930 nm for the ground-state transition. Continuous-wave laser operation was demonstrated at 1083 nm and 932 nm. At 1083 nm, a maximum output power of 1.6 W with a slope efficiency of 64% were achieved under Ti:sapphire-pumping at 804 nm. Our results confirm that Nd:LuAP is a promising gain medium for efficient 1083 nm laser sources for atmospheric helium LiDAR, while highlighting remaining challenges in the crystal growth of this material.