M. Monerie

Bio: M. Monerie is an academic researcher from CNET. The author has contributed to research in topics: Fiber laser & ZBLAN. The author has an hindex of 17, co-authored 29 publications receiving 1007 citations.

Modeling of pair-induced quenching in erbium-doped silicate fibers

Abstract: It is shown that in low-concentration erbium-doped silicate fibers (below 1000 p.p.m.), a residual absorption at 980 nm cannot be saturated. Usual models for upconversion of Er/sup 3+/ cannot match this behavior nor explain a fluorescence lifetime independent of pump power and erbium concentration. A phenomenon, the pair induced quenching (PIQ), that is compatible with the previous experimental results is exhibited. The influence of erbium and aluminum concentration on the ion pair proportion is shown. >

Tunable CW lasing around 0.82, 1.48, 1.88 and 2.35 μm in thulium-doped fluorozirconate fibre

Abstract: Tunable CW operation of a thulium-doped fluorozirconate fibre laser around 0.82 μm, 1.48 μm, 1.88 μm and 2.35 μm is reported. The fibre is single mode above 1.7 μm. Laser dynamics and competition or collaboration between these wavelengths are examined.

Tunable CW lasing around 610, 635, 695, 715, 885 and 910 nm in praseodymium-doped fluorozirconate fibre

Abstract: CW lasing operation of a praseodymium-doped fluorozirconate fibre laser at 610, 635, 695, 715, 885 and 910 nm is reported, together with large tunability domains around these wavelengths. Output powers in excess of 20 mW at 610 nm, 50 mW at 715 nm and 100 mW at 635 nm, with a photon efficiency larger than 50%, have been obtained.

Amplification and lasing at 1.3 mu m in praseodymium-doped fluorozirconate fibres

Abstract: Light emission from the /sup 1/G/sub 4/ to /sup 3/H/sub 5/ transition around 1.3 mu m of Pr/sup 3+/ has been studied in fluoride glass (ZBLAN) fibres. Pumping at 1064 nm yields extracted laser power of a few mW at 1.294 mu m. Gain curves centred at 1.295 mu m have been obtained, with gross gains of more than 15 dB at 1.319 mu m. Changes of the output ASE with pumping conditions are explained by excited state absorption or energy transfer from the /sup 1/G/sub 4/ upper level of the transition. >

Red upconversion Yb-sensitised Pr fluoride fibre laser pumped in 0.8 mu m region

Abstract: Room temperature upconversion lasing has been obtained at 635 nm in Yb : Pr codoped fluoride fibre pumped in the 0.8μm region. Yb3+ is excited by ground state absorption and transfers energy to the 1G4 level of Pr3+, which is then brought into the 3P0 level by excited state absorption. Extracted powers in excess of 20 mW at 635 nm and a slope efficiency of 10% were observed for 840–850 nm.

Upconversion and Anti-Stokes Processes with f and d Ions in Solids

Abstract: Before the 1960s, all anti-Stokes emissions, which were known to exist, involved emission energies in excess of excitation energies by only a few kT. They were linked to thermal population of energy states above excitation states by such an energy amount. It was the well-known case of anti-Stokes emission for the so-called thermal bands or in the Raman effect for the well-known anti-Stokes sidebands. Thermoluminescence, where traps are emptied by excitation energies of the order of kT, also constituted a field of anti-Stokes emission of its own. Superexcitation, i.e., raising an already excited electron to an even higher level by excited-state absorption (ESA), was also known but with very weak emissions. These types of well-known anti-Stokes processes have been reviewed in classical textbooks on luminescence.1 All fluorescence light emitters usually follow the well-known principle of the Stokes law which simply states that excitation photons are at a higher energy than emitted ones or, in other words, that output photon energy is weaker than input photon energy. This, in a sense, is an indirect statement that efficiency cannot be larger than 1. This principle is

Fiber Bragg gratings

Abstract: Since the discovery of photosensitivity in optical fibers there has been great interest in the fabrication of Bragg gratings within the core of a fiber. The ability to inscribe intracore Bragg gratings in these photosensitive fibers has revolutionized the field of telecommunications and optical fiber based sensor technology. Over the last few years, the number of researchers investigating fundamental, as well as application aspects of these gratings has increased dramatically. This article reviews the technology of Bragg gratings in optical fibers. It introduces the phenomenon of photosensitivity in optical fibers, examines the properties of Bragg gratings, and presents some of the important developments in devices and applications. The most common fabrication techniques (interferometric, phase mask, and point by point) are examined in detail with reference to the advantages and the disadvantages in utilizing them for inscribing Bragg gratings. Reflectivity, bandwidth, temperature, and strain sensitivity of the Bragg reflectors are examined and novel and special Bragg grating structures such as chirped gratings, blazed gratings, phase-shifted gratings, and superimposed multiple gratings are discussed. A formalism for calculating the spectral response of Bragg grating structures is described. Finally, devices and applications for telecommunication and fiber-optic sensors are described, and the impact of this technology on the future of the above areas is discussed.

Fundamentals of Coherent Optical Fiber Communications

Abstract: The recently developed digital coherent receiver enables us to employ a variety of spectrally efficient modulation formats such as $M$ -ary phase-shift keying and quadrature-amplitude modulation. Moreover, in the digital domain, we can equalize all linear transmission impairments such as group-velocity dispersion and polarization-mode dispersion of transmission fibers, because coherent detection preserves the phase information of the optical signal. This paper reviews the history of research and development related to coherent optical communications and describes the principle of coherent detection, including its quantum-noise characteristics. In addition, it discusses the role of digital signal processing in mitigating linear transmission impairments, estimating the carrier phase, and tracking the state of polarization of the signal in coherent receivers.

Polarization-maintaining fibers and their applications

Abstract: Polarization-maintaining fibers and their applications are reviewed. The classification of high-birefringent fibers and low-birefringent fibers and their fabrication methods and characteristics are discussed in Section II. Analytical methods and numerical methods for fiber design on the birefringence are presented in Section III. Degradation factors of polarization maintenance expressed as crosstalk or mode-coupling parameters caused by internal origins such as structural imperfections, wavelength, and nonlinear effects, and by external origins such as temperature fluctuations, mechanical perturbations, and electromagnetic effects, are discussed in Section IV. Characterization methods on beat length, mode coupling, stress distribution, and mechanical strength are presented in Section V. Applications to the fiber devices and nonlinear effects, and splicing methods for the polarization-maintaining fibers are described in Sections VI and VII.

Ytterbium-doped silica fiber lasers: versatile sources for the 1-1.2 /spl mu/m region

Abstract: Ytterbium-doped silica fibers exhibit very broad absorption and emission bands, from /spl sim/800 nm to /spl sim/1064 nm for absorption and /spl sim/970 nm to /spl sim/1200 nm for emission. The simplicity of the level structure provides freedom from unwanted processes such as excited state absorption, multiphonon nonradiative decay, and concentration quenching. These fiber lasers therefore offer a very efficient and convenient means of wavelength conversion from a wide variety of pump lasers, including AlGaAs and InGaAs diodes and Nd:YAG lasers. Efficient operation with narrow linewidth at any wavelength in the emission range can be conveniently achieved using fiber gratings. A wide range of application for these sources can be anticipated. In this paper, the capabilities of this versatile source are reviewed. Analytical procedures and numerical data are presented to enable design choices to be made for the wide range of operating conditions. >