Method of manufacturing a laser gain medium having a spatially variable gain profile

Abstract

Method of manufacturing a laser medium with a material having a surface and a dopant in the material distributed whereby the material has a spatially variant optical flux density profile uses tailored non-uniform gain profiles within a Yb:YAG laser component (rod, slab, disc, etc.) achieved by a spatial material modification in the spatially masked pre-forms. High temperature-assisted reduction leads to the coordinate-dependent gain profiles, which are controlled by the topology of the deposited solid masks. The gain profiles are obtained by reducing the charge state of the laser-active trivalent Ybions into inactive divalent Ybions. This valence conversion process is driven by mass transport of ions and oxygen vacancies. These processes, in turn, affect the dopant distribution throughout the surface and bulk laser crystal. By reducing proportionally more Ybions at the unmasked areas of component, than in the masked areas, the coordinate-dependent or spatially-controlled gain profiles are achieved. The material can be used for the fabrication of laser rods, slabs, etc. with various concentrations and spatial localizations of dopants.