Study on the Dynamic Control of Spherical Aberration on the Stable Zone of the First Three Low-Order Modes of LD End-Pumped Lasers

The stable zones of the first three low-order modes of the LD end-pumped laser dynamically controlled by spherical aberration are proposed. Considering the temperature dependence of thermal conductivity, an aberration factor representing spherical aberration is calculated. Based on the multiples of the thermal focal lengths of the fundamental mode, TEM01 and TEM10, their dynamic stable zones were confirmed. An asymmetrical LD end-pumped Nd:YVO4 laser wavefront information measurement experiment was performed. The primary spherical aberration, the beam quality factor and the output power were measured, and their changes with the pumping power were analyzed to determine the dynamic stable zone. The experimental results agree well with the theoretical simulations.