Mid-infrared supercontinuum generation in a fluoroindate fiber with 1.4 W time-averaged power

Abstract

A mid-infrared supercontinuum generation in a step-index fluoroindate fiber pumped by a Tm-doped fiber amplifier seeded with 1.55 µm pulses is reported for the first time. By pumping a 9 µm core fluoride fiber with 3.7 W of power, a broadband supercontinuum with a total output power of 1.41 W and a spectrum extending to 4.1 µm was demonstrated. It is believed that this is the broadest mid-infrared supercontinuum spectrum with Watt-level timeaveraged power generated out of a fluoroindate fiber. The impurities incorporated in the fiber are identified as the main limitation in terms of output power scaling up.

Watt-level and spectrally flat mid-infrared supercontinuum in fluoroindate fibers

“…The spectral fluence was measured with a PbSe detector for wavelengths between 1 μm and 4.8 μm and with a liquid nitrogen cooled HgCdTe detector from 2 μm to 13 μm. A set of long-pass filters was properly used in order to [12] Er-ZBLAN fiber amplifier injected in 13.5 μm core InF 3 fiber 2.5-5.3 0.008 [13] 70 ps OPO (λ c 2.02 μm) injected in 9 μm core InF 3 fiber 1.9-5.3 0.008 [23] 100 fs Tm-doped silica fiber laser injected in 7 μm core InF 3 fibers 1.25-4.2 0.25 [6] 100 ns Tm-doped silica fiber laser injected in 16.7 μm core InF 3 fibers 1.9-2.4 1.02 [24] 1 ns Er-doped and Tm-doped silica fiber injected in 9 μm core InF 3 fiber 1.87-3.9 1.4 [25] 35 ps Tm-doped silica fiber injected in 9 μm core InF 3 fiber 1. block any higher diffraction orders of the grating from overlapping with the SC profile. The complete spectral response was calibrated with a blackbody radiation source (IR-508, Infrared Systems) for each combination of a detector and a long-pass filter.…”

“…As shown in Table 1, there have been few demonstrations of infrared SC generation with fluoroindate fibers [6,[11][12][13][23][24][25][26] with some of them standing out due to their output powers or spectral bandwidths. Furthermore, SC flatness, which is important for many applications, has often been neglected.…”

“…Furthermore, SC flatness, which is important for many applications, has often been neglected. Previous works [6,[24][25][26] reported that InF 3 fibers can sustain high average powers, while [13] showed that broadband and high spectral flatness MIR SC can be achieved by injecting picosecond laser pulses with a central wavelength around 2 μm.…”

Numerical simulation of coherent mid-infrared supercontinuum generation based on carbon chloride core tapered photonic crystal fibers

“…Fiber-based coherent mid-infrared (MIR) supercontinuum (SC) source has important applications in molecular spectroscopy, biomedicine, optical coherence tomography, remote sensing, national defense and security [1][2][3][4][5][6]. To generate MIR-SC, much attention has been paid to non-silica fibers such as tellurite, fluoride, and chalcogenide fibers with low transmission loss in MIR region [7][8][9][10][11][12][13]. However, the use of these soft fibers as nonlinear medium has limitations of difficult preparation and high cost.…”

Broadband and top-flat mid-infrared supercontinuum generation with 3.52 W time-averaged power in a ZBLAN fiber directly pumped by a 2-µm mode-locked fiber laser and amplifier

“…When mid-IR spectral region is concerned, soft glass fibers, including tellurite [5,6], fluoride [1,[7][8][9][10][11][12] and chalcogenide [13,14] fibers can be adopted as nonlinear media. However, among all soft glass fibers, only heavy metal fluoride fibers, including fluorozirconate (ZBLAN) [15][16][17][18][19] and fluoroindate (InF 3 ) [20,21] are technologically mature to be used for multi Watt level SC generation. Because they exhibit a zero-dispersion wavelength (ZDW) within the range of ~ 1.5-1.9 µm they can be effectively pumped in the anomalous dispersion region, which facilitates efficient continuum extension towards longer wavelengths.…”