Direct Generation of Vortex Laser by Rotating Induced Off-Axis Pumping

We propose a simple method for direct generation of vortex laser based on all-solid-state laser technology. Diagonal HG01 mode is first achieved by rotating the Nd:YVO4 gain medium in xz plane. Further rotating the gain medium (in yz plane) leads to mode conversion from diagonal HG 01 to LG01. A simple home-made interference device has been used to verify the vortical property of the LG01 mode with well-determined handedness. The generated LG01 mode has a maximum output power of 2.85 W and slope efficiency of about 41.1%, which indicate that the present method is very efficient. Moreover, this method has good universality and can be used for the generation of other solid state vortex lasers, which paves the way toward simple, reliable, and efficient generation of vortex lasers for various applications.