A rib waveguide structure in AsSe chalcogenide glass has been designed and numerically analyzed for on-chip coherent supercontinuum generation in the midinfrared region. The waveguide structure possesses an all-normal dispersion profile with dispersion value of -13.22  ps/nm·km at the pump wavelength. Coherent midinfrared supercontinuum spectrum spanning 1.2 to 7.2 μm has been obtained using a 2.5 mm long rib waveguide when pumped with 200 fs laser pulses of a peak power of 2.5 kW and a repetition rate of 1 kHz at 2.8 μm. Such highly nonlinear subwavelength size rib waveguide structures are highly applicable for the power efficient on-chip midinfrared coherent supercontinuum sources. Coherent midinfrared supercontinuum sources are very important in frequency metrology, nonlinear microscopy, nondestructive testing, molecular spectroscopy, and optical coherence tomography.

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We demonstrate a coherent mid-infrared supercontinuum generation in a step-index tellurite fiber with an all-normal dispersion profile. A coherent supercontinuum spectrum spanning 1340–2840 nm in a 6.3-cm-long tellurite step-index fiber is obtained when the fiber is pumped with 200 fs laser pulses with a coupled peak power of 5.5 kW at 2000 nm. Such fiber-based coherent mid-infrared supercontinuum sources are highly required for the imaging of biological tissues in optical coherence tomography, pump–probe spectroscopy, pulse compression, and sensing.

We report on mid-infrared gas spectroscopy measurements by means of the supercontinuum absorption spectroscopy method. We developed a 80-MHz-repetition-rate mid-infrared supercontinuum light source with an average power of 40 mW generated through nonlinear propagation of 200-fs pulses in a 10-cm-long segment of step-index tellurite fiber. A compact multipass cell is used for analyzing absorption of CO2 and CH4 gases and their mixture in the 2-3.5µm spectral range. Experimental results are compared to the HITRAN database.

A numerical investigation on chalcogenide W-type co-axial optical fiber structures is reported for broadband highly coherent mid-IR supercontinuum generation. The structural parameters of the optical fiber were optimized to achieve small normal dispersion in a broad spectral range of the mid-IR region. The W-type optical fiber structure possesses a flat chromatic dispersion profile with the flatness of the dispersion variation of ±2.45 ps/nm/km within the spectral range of 4.9–12.6 μm. A coherent mid-IR supercontinuum spectrum spanning 2.28 to 15.52 μm at the −40 dB level is obtained using a 4 cm long W-type optical fiber when it pumped by a 200 fs laser pulse with a peak power of 10 kW at 7.0 μm. Broadband coherent mid-infrared supercontinuum sources have potential applications in frequency metrology, nonlinear microscopy, non-destructive testing, optical coherence tomography, and molecular spectroscopy.