Watt-Level Pr3+:LiYF4 Novel Green Lasers at 519 nm, 538 nm, and 550 nm

We report the first demonstration on three new wavelengths of 519 nm, 538 nm, 550 nm in the $\sigma $ -polarized direction based on continuous-wave (CW) Pr3+:LiYF $_{\mathbf {4}}$ laser. The transitions mechanism combined dual upper energy levels of $^{3}\text{P}_{\mathbf {1}}$ and $^{3}\text{P}_{\mathbf {0}}$ with Stark sub-levels of $^{3}\text{H}_{\mathbf {5}}$ was proposed. The CW lasers achieve output power greater than watt levels in the $\sigma $ -polarized direction at room temperature, with 1.21 W at 519 nm, 1.45 W at 538 nm, and 1.06 W at 550 nm.