Highly efficient Yb:YAG microchip laser for direct generation of radially polarized vector vortices

High beam quality, highly efficient radially polarized vector vortex beam has been generated in a Yb:YAG microchip laser pumped with an annular beam formed with a hollow focus lens. The output power of 2.15 W has been achieved at the absorbed pump power of 3.53 W. The optical-to-optical efficiency is 60.9%. The radially polarized vector vortex lasers working at 1030 nm, 1050 nm, 1030/1050 nm dual-wavelength depending on applied pump power. High polarization purity with degree of polarization of over 91% has been achieved for radially polarized vector vortex lasers. Our work provides an effective method for developing compact wavelength tunable, radially polarized vector vortex lasers.