Few-moded ultralarge mode area chalcogenide photonic crystal fiber for mid-infrared high power applications

We demonstrate a novel few-moded ultralarge mode area chalcogenide glass photonic crystal fiber for mid-infrared high power applications. The numerical simulation indicates that the fiber has ultralarge mode areas of similar to 10500 mu m(2) and similar to 12000 mu m(2) for the fundamental mode LP01 and the lowest higher-order mode LP11, respectively. Dual-moded operation is confirmed experimentally at 2 mu m, in good agreement with the numerical simulation. By selectively launching technique, low bending loss of 0.7 dB/m, equivalent to 0.55 dB/turn, has been observed in the fiber with a small bending radius of similar to 12 cm, indicating excellent bending resistance of the few-moded fiber with such a large mode area. The fiber has been demonstrated to sustain an incident power density up to 150 kW/cm(2) under 2-mu m CW laser irradiation, showing the potential of the fiber for high-power applications in mid-infrared. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement