Coherent Mid-infrared Supercontinuum Generation Research Articles

Super-flat coherent supercontinuum source in As38.8Se61.2 chalcogenide photonic crystal fiber with all-normal dispersion engineering at a very low input energy.

We numerically report super-flat coherent mid-infrared supercontinuum (MIR-SC) generation in a chalcogenide As38.8Se61.2 photonic crystal fiber (PCF). The dispersion and nonlinear parameters of As38.8Se61.2 chalcogenide PCFs by varying the diameter of the air holes are engineered to obtain all-normal dispersion (ANDi) with high nonlinearities. We show that launching low-energy 50 fs optical pulses with 0.88 kW peak power (corresponding to pulse energy of 0.05 nJ) at a central wavelength of 3.7 μm into a 5 cm long ANDi-PCF generates a flat-top coherent MIR-SC spanning from 2900 to 4575 nm with a high spectral flatness of 3 dB. This ultra-wide and flattened spectrum has excellent stability and coherence properties that can be used for MIR applications such as medical diagnosis of diseases, atmospheric pollution monitoring, and drug detection.

Coherent mid-infrared supercontinuum generation in all-solid chalcogenide microstructured fibers with all-normal dispersion.

We report the coherent mid-infrared supercontinuum generation in an all-solid chalcogenide microstructured fiber with all-normal dispersion. The chalcogenide microstructured fiber is a four-hole structure with core material of AsSe2 and air holes that are replaced by As2S5 glass rods. Coherent mid-infrared supercontinuum light extended to 3.3 μm is generated in a 2 cm long chalcogenide microstructured fiber pumped by a 2.7 μm laser.

Coherent mid-infrared supercontinuum generation with As2Se3 photonic crystal fiber and femtosecond Airy pulses

We discuss a novel method for generating hyper-broadband mid-infrared (MIR) supercontinua (SC) with coherent bandwidth from ~2 μm to ~10 μm by using As2Se3 photonic crystal fiber (PCF) and a 4.1 μm pump with femtosecond (fs) Airy pulse profile. Our simulations confirm that, when pumping in the normal dispersion region, the deceleration and self-healing properties of the Airy pulse can suppress the incoherent noise in modulational instability (MI) induced SC generation and maintain the pulse coherence over a long propagation distance. We also find that fs Airy pulse can generate an MIR SC with a broader coherent bandwidth than these can be achieved with fs parabolic secant pulse.

Highly nonlinear tapered photonic crystal fibers for broadband mid-infrared supercontinuum generation in the few-optical-cycle regime

We propose a design of tellurite and As2S3-based chalco- genide tapered photonic crystal fibers (TPCF) for broadband coherent mid-infrared supercontinuum (SC) generation in the few-optical-cycle regime. We optimize the soliton self-compression by injecting pre-chirped femtosecond pulses. More than one octave-spanning SC spectra were generated in 8 mm-long in both tellurite and chalcogenide TPCF with low input pulse energies of 1 nJ and 100 pJ at pump wavelengths of 2.9 and 4.7 μm, respectively. © 2012 Society of Photo-Optical Instrumentation