Enhanced supercontinuum generation in tapered tellurite suspended core fiber

• Development of tapered tellurite suspended core fiber for supercontinuum generation.
• Group-velocity matching dynamics in tapers are exploited for enhanced supercontinuum.
• Experimental evidence of 400-THz (0.6–3.3 µm) bandwidth supercontinuum generation.

We demonstrate 400-THz (0.6–3.3 µm) bandwidth infrared supercontinuum generation in a 10 cm-long tapered tellurite suspended core fiber pumped by nJ-level 200-fs pulses from an optical parametric oscillator. The increased nonlinearity and dispersion engineering extended by the moderate reduction of the fiber core size are exploited for supercontinuum optimization on both frequency edges (i.e., 155-THz overall gain), while keeping efficient power coupling into the untapered fiber input. The remaining limitation of supercontinuum bandwidth is related to the presence of the high absorption beyond 3 µm whereas spectral broadening is expected to fully cover the glass transmission window (0.5–4.5 µm).