Mid-Infrared Self-Similar Pulse Compression in a Tapered Tellurite Photonic Crystal Fiber and Its Application in Supercontinuum Generation

Abstract

In this paper, we design a tapered tellurite photonic crystal fiber (TTPCF) with nonlinear coefficient increasing along the propagation direction, and demonstrate the mid-infrared self-similar pulse compression of the fundamental soliton in such a TTPCF. When the variation of group-velocity dispersion, higher-order dispersion, higher-order nonlinearity, and linear loss are considered, a 1 ps pulse at wavelength 2.5 μm can be compressed to 62.16 fs after a 1.63-m long propagation, along with the negligible pedestal, compression factor Fc of 16.09, and quality factor Qc of 83.16%. Then the compressed pulse is launched into another uniform tellurite PCF designed, and highly coherent and octave-spanning supercontinuum (SC) is generated. Compared to the initial picosecond pulse, the compressed pulse has much larger tolerance of noise level for the SC generation. Our research results provide a promising solution to realize the fiber-based mid-infrared femtosecond pulse source for nonlinear photonics and spectroscopy. Index Terms-Tapered tellurite photonic crystal fiber, self-similar pulse compression, SC generation. I. INTRODUCTION HE ultrashort pulses can find important applications in supercontinuum (SC) generation, frequency comb generation, biological imaging, and optical communication [1]-[4], etc. Over the past few years, several pulse compression

Multi-octave mid-infrared supercontinuum and frequency comb generation in a suspended As2Se3 ridge waveguide

“…It should be noted that the micron-scale length is not difficult to achieve by using the current waveguide fabrication technique. As the pulse width is increased from 100 to 250 fs, the soliton order, which is related to the pulse width and peak power [8,40], is calculated as 11.2, 16.8, 22.5, and 28.1, respectively. When the pump pulse width is chosen as 100 fs, the soliton separation distance is 0.76 mm.…”

Highly coherent supercontinuum generation in a polarization-maintaining CS2-core photonic crystal fiber

“…A1 (λ, t) and A2 (λ, t), which are obtained from 50 shot-to-shot simulations with different random noises at wavelength λ. We take t1 -t2 = 0 and the random noise is defined as [5,43], where noise amplitude η is chosen as 1 × 10 -3 in our simulation. The cross-section of the PM-CCPCF is shown in Fig.…”

“…In addition, the modulation instability (MI) length LMI is calculated as ~16LNL, which is equal to 1.1, 0.53, 0.33, 0.23, and 0.17 cm for different P0, and much less than the propagation length. However, for narrow pulse of 80 fs, the influence of the MI can be significantly reduced, and good coherence can be still maintained [40,43]. By taking the bandwidth and coherence into consideration, it is found that P0 = 1000 W is the optimum power value.…”

“…The pump pulse is located in the anomalous dispersion region of the PM-CCPCF, so the soliton dynamics play an important role in the spectral broadening. Soliton number is defined as N = (LD/LNL) 1/2 , where the dispersion length LD and nonlinear length LNL are respectively defined as[5],[43]…”

Chalcogenide–Tellurite Composite Photonic Crystal Fiber: Extreme Non-Linearity Meets Large Birefringence

“…To realize non-linear processes with low powers and in short interaction lengths, non-silica photonic crystal fibers (PCFs) made of high-index glasses such as tellurite [8], bismuth-oxide [9], and chalcogenide glasses [10] as well as PCFs filled with high-index liquids such as carbon-disulfide [11,12] are designed, studied and fabricated. Among different materials, chalcogenide glasses with a large refractive index of around 3, ultra-high non-linear refractive index of 3 × 10 −18 m 2 /W, and a high transmission window from 0.6 to 15 µm, open up new possibilities to design and develop compact non-linear devices [13].…”