Ultra-broadband mid-infrared supercontinuum generation in photonic-crystal pillar waveguides pumped at 1.82 μm

In this paper, we theoretically investigate the supercontinuum generation (SCG) spanning from near-infrared (NIR) to mid-infrared utilizing a novel photonic-crystal pillar waveguide (PCPW). The PCPW design and associated dispersion properties have been thoroughly studied and optimized, resulting in a flat and low dispersion profile from 1.67 to 7.31 µm with four zero dispersion wavelengths. Pumped at a relatively shorter NIR wavelength of 1.82 µm, the SCG of optimized PCPW possesses an ultra-broadband spectral broadening from 1 to 10 µm under pump pulses with a low peak power of 2 kW. The proposed PCPW can thus provide an efficient waveguide structure to generate ultra-broadband supercontinuum pumped by shorter wavelength laser sources of less peak power.