High-power single-frequency handedness switchable vortex laser from an off-axis pumped Er:YAG nonplanar ring...

We demonstrate a high-power single-frequency, handedness-switchable vortex laser at 1645 nm, directly generated from an off-axis pumped Er:YAG nonplanar ring oscillator. Narrow-linewidth Laguerre-Gauss (LG) modes of orders -2, -1, +1, and +2 are obtained, with output powers of 4.53 W, 7.09 W, 7.03 W and 4.58 W, respectively. The linewidth of the LG_0,+2 mode is measured to be 3.4 kHz. This work provides a compact and high-power vortex laser suitable for applications such as optical remote sensing.