1.7μm fiber gas Raman laser based on sulfur-hexafluoride-filled anti-resonant hollow-core fibers

We demonstrated a 1.7 μm pulsed near-infrared fiber gas Raman laser (FGRL) based on sulfur hexafluoride (SF₆)-filled anti-resonant hollow-core fibers (AR-HCFs). Pumped by a customized 1.5 μm erbium-doped fiber amplifier (EDFA), firstorder Stokes laser with a wavelength of 1748 nm was obtained. Through the special design of the AR-HCF, the transmission losses of the pump laser and Stokes laser in it were reduced to as low as 0.2 dB/km and 3.17 dB/km, respectively. When the pressure of SF₆ gas was 19 bar and the pulse repetition frequency was 750 kHz, the maximum Stokes power was approximately 2.3 W, with a corresponding optical-to-optical conversion efficiency of about 16.8%.