High-power vertical-cavity surface-emitting lasers for solid-state laser pumping

Vertical-cavity surface-emitting lasers (VCSELs) have emerged as a promising candidate for pumping of solid-state lasers, as they can be configured into high-power two-dimensional arrays and modules of arrays. VCSELs emit in a circular, uniform beam which can greatly reduce the complexity and cost of coupling optics. Their narrow and stable emission spectrum is well suited to the narrow absorption spectrum generally observed for solid-state gain media. The superior reliability of VCSELs greatly enhances the robustness of solid-state laser systems and enables high-temperature operation. In this work, we discuss recent developments on kW-class VCSEL pumps for solid-state lasers. Results on VCSEL modules designed for end-pumping and for side-pumping are presented. More than 4kW in CW operation is demonstrated from a multi-array VCSEL module. We also present results on solid-state lasers using VCSEL modules as pumps. In an end-pumping configuration, more than 250W peak power at 1064nm is demonstrated, and in a side-pumping Q-switched configuration, more than 21mJ at 946nm is demonstrated for an Nd:YAG solid-state laser.