Compact all-fiber hundred-microjoule nanosecond laser at 911 nm

Motivated by the demand of water vapor differential absorption lidar (DIAL), we demonstrate a compact all-fiber nanosecond laser at 911 nm with over hundred-microjoule (μJ) pulse energy based on homemade Nd-doped silica fiber, which consists of a nanosecond pulse seed and two stage amplifiers. The seed pulse was generated by modulating a temporally stable continuous-wave Nd-doped fiber laser with an acousto-optic modulator. To avoid the pulse narrowing in the energy scaling process, temporal pre-shaping was applied to the seed using a triangular wave with an inverse exponential profile. The system ultimately achieved a laser output with a pulse energy of 148 μJ and a pulse width of 162 ns at a repetition rate of 50 kHz. The M 2 was measured to be 1.04. These results provide a simplified scheme for constructing compact all-fiber nanosecond lasers at 0.9 μm with over 100 μJ pulse energy, showing potential for applications in water vapor DIAL.