Controlling the handedness of directly excited Laguerre-Gaussian modes in a solid-state laser

摘要

In this Letter, we report a novel approach for directly exciting the lowest-order Laguerre-Gaussian (LG_(01)) donut mode with controllable handedness of the helical phase front trajectory in an end-pumped solid-state laser. Our approach is based on the use of a novel mode selection element consisting of two nanoscale thickness aluminum stripes to provide discrimination between LG_(01) modes with opposite handedness. This scheme has been applied to a diode-pumped Nd:YAG laser to generate and switch between LG_(01) modes with opposite handedness at output powers ～1 W at 1064 nm.