Tunable single-longitudinal-mode operation of a sandwich-type YAG/Ho:YAG/YAG ceramic laser

High power single-longitudinal-mode Ho3+:YVO4 unidirectional ring laser

“…It has important applications in the areas of laser lidar, high resolution spectroscopy, and achieving 3-12 μm lasers [1,2] . So far, many configurations have been applied to achieve the single-longitudinal-mode lasers near 2 μm, such as the coupled cavity laser [3] , twisted-modecavity laser [4] , the microchip laser [5] , the nonplanar ring laser, the intracavity etalons laser [6] , etc. Among them, the nonplanar ring laser [7,8] and twisted-mode-cavity laser [9] are two common ways to obtain high power singlelongitudinal-mode operation, while they are applicable to only isotropic gain medium and are difficult for achieving single-longitudinal-mode operation with a long cavity length, which result in limiting the narrower linewidth output.…”