Watt-Level Single-Frequency Pr:LiY_0.3Lu_0.7F₄ Mixed Crystal Laser in Red Spectral Region

We report on the first watt-level single frequency all-solid-state Pr3+-doped laser operating in continuous-wave mode based on ring cavity method. The achieved red (639.52 nm) single frequency laser has a maximum output power of 1.19 W at an absorbed power of 5.91 W with a slope efficiency of about 24.9%. Linewidth of the single frequency was measured to be about 20 MHz. By inserting an F-P etalon into the ring cavity, we also obtained a dual-wavelength laser (639.22+639.63 nm) still operating in single longitudinal mode. This dual-wavelength single-longitudinal-mode laser has the potential to generate a microwave source. In comparison to a conventional method for obtaining single frequency laser in visible through frequency doubling, using Pr3+-doped materials combined with single frequency laser technology to directly obtain visible single-longitudinal-mode laser has certain advantages in simplicity, miniaturization, high efficiency and cost efficiency of the total system.