title: Multi-Fresnel lenses pumping approach for improving high-power Nd:YAG solar laser beam quality.
abstract: To significantly improve the present-day high-power solar laser beam quality, a three-stage multi-Fresnel lenses approach is proposed for side-pumping either a Nd:YAG single-crystal or a core-doped Sm(3+)Nd:YAG ceramic rod. Optimum pumping and laser beam parameters are found through ZEMAX and LASCAD numerical analysis. The proposed scheme offers a uniform absorption profile along the rod. 167 W laser power can be achieved, corresponding to 29.3 W/m(2) collection efficiency. High brightness figure of merit of 8.34 W is expected for the core-doped rod within a convex-concave resonator, which is 1300 times higher than that of the most-recent high-power solar laser.
authors.affiliation: CEFITEC, Departamento de Física, FCT, Universidade Nova de Lisboa, 2829-516 Campus de Caparica, Portugal. dl@fct.unl.pt
authors.forename: Dawei
authors.initials: D
authors.lastname: Liang
authors.forename: Joana
authors.initials: J
authors.lastname: Almeida