The first demonstration of a compact high-power 320-nm continuous-wave single-frequency ultraviolet laser based on power scaling of diode-pumped Pr:LiYF4 ring laser at red

Single-frequency (SF) lasers in the visible spectral region are usually obtained through an indirect method, i.e., frequency doubling of near-infrared SF lasers. In this work, we report on the direct generation of a high-power continuous-wave (CW) SF laser in red based on a diode-pumped Pr:LiYF