Amira Baili

Bio: Amira Baili is an academic researcher from Carthage University. The author has contributed to research in topics: Photonic-crystal fiber & Supercontinuum. The author has an hindex of 4, co-authored 13 publications receiving 57 citations.

Design and analysis of equiangular spiral photonic crystal fiber for mid-infrared supercontinuum generation

Abstract: A design of equiangular spiral photonic crystal fiber (PCF) in As2Se3 chalcogenide glass is reported for mid-infrared supercontinuum generation. Supercontinuum covering the 1.2–15 μm molecular fingerprint region is achieved using only 8 mm long designed PCF pumped with 50 fs laser pulses of 500 W peak power. The structural parameters have been tailored for all-normal dispersion characteristic. Proposed structure has high nonlinearity (γ = 12474 W−1 km−1) at 3.5 μm with very low and flat dispersion −2.9 [ps/(nm × km)]. Supercontinuum with such broadening and high coherence degree is applicable for mid-infrared spectroscopy, gas sensing, early cancer diagnostics and free space communication.

Maximizing the bandwidth of coherent, mid-IR supercontinuum using highly nonlinear aperiodic nanofibers

Abstract: We describe in detail a new procedure of maximizing the bandwidth of mid-infrared (mid-IR) supercontinuum (SC) in highly nonlinear microstructured As2Se3 and tellurite aperiodic nanofibers. By introducing aperiodic rings of first and secondary air holes into the cross-sections of our microstructured fiber designs, we achieve flattened and all-normal dispersion profiles over much broader bandwidths than would be possible with simple periodic designs. These fiber designs are optimized for efficient, broadband, and coherent SC generation in the mid-IR spectral region. Numerical simulations show that these designs enable the generation of a SC spanning over 2290 nm extending from 1140 to 3430 nm in 8 cm length of tellurite nanofiber with input energy of E = 200 pJ and a SC bandwidth of over 4700 nm extending from 1795 to 6525 nm generated in only 8 mm-length of As2Se3-based nanofiber with input energy as low as E = 100 pJ. This work provides a new type of broadband mid-IR SC source with flat spectral shape as...

Two octaves spanning supercontinuum in highly nonlinear As 2 Se 3 nanophotonic crystal fiber for midinfrared applications

Abstract: A new design of all-normal and near-zero flattened dispersion based on chalcogenide nanophotonic crystal fiber (PCF) has been proposed to generate smooth and ultra-broadband supercontinuum (SC) in the midinfrared (IR) region. With the optimized geometric parameters, the As2Se3 nano-PCF has been found to be suitable for two-octave supercontinuum generation (SCG). We designed a nano-PCF having a flat top dispersion curve with a maximum value of −2.3 [ps/(nm km)] and a large nonlinear coefficient equal to 7250 (W km)−1 around the wavelength of 5.24 μm. By numerical simulations, we predict the generation of a very broadband SC in the mid-IR region extending from 2 to 10 μm in only 2-mm fiber lengths by using a femtosecond laser having a full-width at half-maximum of 50 fs and a relatively low energy of E=80 pJ. The generated SC demonstrates perfect coherence property over the entire bandwidth. SC generation extended into the mid-IR spectral region has potential usefulness in a variety of applications requiring a broad and mid-IR spectrum, such as WDM sources, fiber sensing, IR spectroscopy, fiber laser, and optical tomography coherence.

New design of As2Se3-based chalcogenide photonic crystal fiber for ultra-broadband, coherent, mid-IR supercontinuum generation

Abstract: In this paper, we propose a new design of all-normal and ultra-flat dispersion As2Se3-based chalcogenide photonic crystal fibers (PCF) The generation of supercontinuum (SC) in the designed fibers is investigated, which has flat and smooth profile, covers a broad range extending from 2 to 8 μm The significance of this work is that it provides a new type of mid-infrared SC source with flat shape, broadband and high coherence properties by pumping the As2Se3-based PCF Thus many applications can be performed such as fiber lasers, pulse compression and multi-wavelength optical sources in the mid-infrared region

Ultra-broadband, mid IR and coherent supercontinuum generated in aperiodic chalcogenide photonic crystal fibers

Abstract: A new design of aperiodic As2Se3-based chalcogenide photonic crystal fibers (PCF) is proposed in order to obtain broadband, mid-IR, and coherent supercontinuum (SC) sources. The proposed fibers possess an ultra-flattened dispersion curve over a wide wavelength range. The significance of this work is that it provides a new type of midinfrared SC source with flat shape, broadband and high coherence properties by femtosecond pumping the As2Se3-based PCF. The generated SC in the designed fibers cover a broadband range extending from 2 μm to more than 8 μm with a low input energy of 120 pJ and a short fiber length of 16 mm. In this context, many applications can be performed such as fiber lasers, pulse compression and multi-wavelength optical sources in the mid-infrared region.

Supercontinuum generation, photonic crystal fiber

Abstract: A topical review of numerical and experimental studies of supercontinuum generation in photonic crystal fiber is presented over the full range of experimentally reported parameters, from the femtosecond to the continuous-wave regime. Results from numerical simulations are used to discuss the temporal and spectral characteristics of the supercontinuum, and to interpret the physics of the underlying spectral broadening processes. Particular attention is given to the case of supercontinuum generation seeded by femtosecond pulses in the anomalous group velocity dispersion regime of photonic crystal fiber, where the processes of soliton fission, stimulated Raman scattering, and dispersive wave generation are reviewed in detail. The corresponding intensity and phase stability properties of the supercontinuum spectra generated under different conditions are also discussed.

Broadband Mid-Infrared Supercontinuum Spectra Spanning 2-15 μm Using As 2 Se 3 Chalcogenide Glass Triangular-Core Graded-Index Photonic Crystal Fiber

Abstract: In this paper, we report analysis, design, and numerical modeling of mid-infrared supercontinuum generation across 2-15 μm molecular “fingerprint region” using a new design of triangular-core graded-index photonic crystal fiber (PCF) pumped with 50 fs laser pulses of peak power of 3.5 kW at 4.1 μm. Proposed PCF design offers the nonlinear coefficient as high as 1944 W -1 · Km -1 at pump wavelength. To the best of our knowledge, the supercontinuum in PCF with such broadband spectra has been reported first time. Proposed PCF design has potential applications in gas sensing, food quality control, and early cancer diagnostics.

Micro and Nanostructured Materials for the Development of Optical Fibre Sensors.

Abstract: The measurement of chemical and biomedical parameters can take advantage of the features exclusively offered by optical fibre: passive nature, electromagnetic immunity and chemical stability are some of the most relevant ones. The small dimensions of the fibre generally require that the sensing material be loaded into a supporting matrix whose morphology is adjusted at a nanometric scale. Thanks to the advances in nanotechnology new deposition methods have been developed: they allow reagents from different chemical nature to be embedded into films with a thickness always below a few microns that also show a relevant aspect ratio to ensure a high transduction interface. This review reveals some of the main techniques that are currently been employed to develop this kind of sensors, describing in detail both the resulting supporting matrices as well as the sensing materials used. The main objective is to offer a general view of the state of the art to expose the main challenges and chances that this technology is facing currently.