1612-202X/12/9/095102Abstract. Based on acousto-optic modulation and grating diffraction, a high-power-pulsed ~2 μm laser with a wide tunable wavelength is realized in double-clad Tm fibers. A maximum average output power of 35.6 W is obtained with the 6 m fiber, which also provides a maximum pulse energy and peak power of 1.58 mJ and 5.6 kW, respectively. For the 6 m fiber length, a >20 W average power can be achieved over a 100 nm wavelength tuning range. Shortening the fiber length to...