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Mid-Infrared methane (CH4) spectroscopy results were obtained in band III beyond 7 µm. To achieve this, the generation of supercontinuum covering the spectral range between 5 and 12 µm was realized by using purified chalcogenide optical fibers free of highly toxic elements such as arsenic and antimony. Besides a pumping with an optical parametric amplifier, an all fibered pumping scheme has also been investigated. In both configuration, supercontinuum absorption spectroscopy experiments have allowed for CH4 sensing, concentration as low as 14 ppm has been detected.

We experimentally demonstrate that simple tapered Ge-Se-Te glass rods with femtosecond pumping enables efficient multi-octave mid-infrared supercontinuum generation, from 1.7 to 16 µm, while keeping an excellent spatial beam profile.

Mid-infrared supercontinuum sources are particularly important for identifying and characterizing molecules and materials through spectroscopy, thus enabling key applications. We here demonstrate the possibility of combining both mid-IR supercontinuum generation and evanescent wave spectroscopy in a single chalcogenide fiber device by means of heat-and-draw processes to manage linear and nonlinear wave-guiding properties.

We demonstrate spontaneous emission of discretized conical wave when an ultrashort pulse propagates nonlinearly in a multimode fiber. Our theoretical predictions are experimentally and numerically confirmed , providing a general understanding of phase-matched radiations emitted by nonlinear waves in multidimensional dispersive optical system.

We present our recent theoretical and experimental advancements in studying complex multiple nonlinear interactions of coherent solitary wave structures on unstable background – breathers. We use the focusing one-dimensional nonlinear Schrödinger equation (NLSE) as a theoretical model. First, we describe the nonlinear mutual interactions between a pair of co-propagative breathers called breather molecules. Then with the novel approach of breather interaction management, we adjust the initial positions and phases of several breathers to observe various desired wave states at controllable moments of evolution. Our experiments carried out on a light wave platform with a nearly conservative optical fiber system accurately reproduce the predicted dynamics. In addition, we consider generalizations of the scalar breathers theory to the vector two-component NLSE describing polarized light and show examples of resonance vector breathers transformations.

We investigate coherent Kerr combs generation via Brillouin lasing in a non-reciprocal cavity. This approach offers adjustable repetition rates and enhanced coherence. A numerical model is presented that ac-counts for the interplay between Brillouin scattering, Kerr effect, and cavity resonant feedback. Through quan-titative agreement with experiments, our study highlights the importance of mode-pulling effects in setting the comb’s dynamics, which had been overlooked in previous fiber experiments. Finally, we discuss limitations and suggest scaling laws for these systems.

We demonstrate an athermal Brillouin strain sensor using heavily GeO2-doped optical fibers. We also report nonlinear evolution of Brillouin temperature sensitivity as a function of wavelength and strong Brillouin gain in these fibers.

We report on a stabilized single-frequency Brillouin fiber laser operating at 1.06 µm by means of a passive highly nonlinear fiber ring cavity combined with a phase-locking loop scheme. We show significant linewidth narrowing (below 1-kHz) as well as frequency noise reduction compared to that of the initial pump in our mode-hop free Brillouin fiber laser.

Adaptative objects based on shape-memory materials are expected to significantly impact numerous technological sectors including optics and photonics. In this work, we demonstrate the manufacturing of shape-memory optical fibers from the thermal stretching of additively manufactured preforms. First, we show how standard commercially-available thermoplastics can be used to produce long continuously-structured microfilaments with shape-memory abilities. Shape recovery as well as programmability performances of such elongated objects are assessed. Next, we open the way for light-guiding multicomponent fiber architectures that are able to switch from temporary configurations back to user-defined programmed shapes. We strongly expect that such actuatable fibers with light-guiding abilities will trigger exciting progress of unprecedented smart devices in the areas of photonics, electronics, or robotics.

Among the different fundamental aspects that govern the design and development of elongated multimaterial structures via the preform-to-fiber technique, material association methodologies hold a crucial role. They greatly impact the number, complexity and possible combinations of functions that can be integrated within single fibers, thus defining their applicability. In this work, co-drawing strategies to produce monofilament microfibers from unique glass-polymer associations are discussed.

We present theoretical as well as experimental evidence of far-detuned nonlinear wavelength conversion towards the mid-infrared, namely beyond 3.5 µm, in a few-mode graded-index silica fiber pumped at 1.064 µm. We take into account the full frequency-dependence of the propagation constants, which allows us to obtain excellent agreement of theoretical predictions with experimental observations and provides new and accurate interpretation of intramodal and intermodal four-wave mixing processes in few-mode fibers.

We provide a general approach for structuring invariant 3D+1 optical wave packets in both bulk and structured dispersive media, through a simple engineering of phase-matched space-time frequencies on quadric surfaces.