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In the face of acute poverty, financial inclusion is still a topical issue. It aims to lift the poor out of the abyss of exclusion and marginalization. Financial inclusion refers to the proportion of individuals or organizations accessing a range of financial services such as savings, credit, payment instruments and insurance (WB 2015). Thus, financial inclusion appears to be a universal strategy for fighting poverty. This article explores the historical and theoretical contours of financial inclusion through a review of the literature. With a real antiquity, through the pawnshop, financial inclusion has been strengthened over the years in its performance to become widespread in all parts of the world. It has been adopted as an inclusive strategy to fight poverty by providing access to a range of financial services. Even though its purpose is to give the poor the possibility of integrating finance, two approaches with contradictory appearances have come together to feed the theoretical reflection. The most salient elements of their opposition are the quest for rationality and the search for broad social outreach. However, although seemingly contradictory, these approaches converge, while complementing each other, on three determinants that underpin the performance of financial inclusion. These are affordability, use of financial services and quality. These three determinants are discussed in the literature as the foundations of the performance of financial inclusion strategies. As such, they are analyzed in different contexts to determine proven methodologies for their implementation. Keywords: Financial inclusion; Poverty; Approach Classification JEL: G20, G21 Paper type: Theoretical Research &nbsp, Face à l’acuité de la pauvreté, l’inclusion financière se positionne toujours comme une actualité. Elle ambitionne d’extirper les pauvres du gouffre de l’exclusion et de la marginalisation. L’inclusion financière et la proportion d’individus ou d’organisation accédant à des services financiers d’une gamme variée comme l’épargne, le crédit, les moyes de payement et l’assurance (BM, 2015). Ainsi, l’inclusion financière apparait comme une stratégie universelle de lutte contre la précarité. Son exploration à partir d’une revue de la littérature a permis, dans cet article, de dresser ses contours historiques et théoriques. Avec une ancienneté réelle, à travers le mont-de-piété, l’inclusion financière s’est fortifiée au fil des âges dans ses performances pour se généraliser dans toutes les contrées de la planète. Elle est adoptée ainsi comme une stratégie inclusive de lutte contre la pauvreté par l’octroi de capacités d’accès à une gamme de service financier. Même si sa finalité est de donnée aux pauvres, la possibilité d’intégrer les finances, deux approches aux allures contradictoires se sont côtoyées pour alimenter la réflexion théorique. Les éléments les plus saillants de leur opposition sont la quête de la rationalité et la recherche d’une portée sociale étendue. Toutefois, bien qu’apparemment contradictoire ses approches convergent, tout en se complétant, sur trois déterminants qui fonde les performances de l’inclusion financière. Il s’agit en l’occurrence de l’accessibilité financière, l’utilisation des services financiers et enfin le niveau de qualité. Ces trois déterminants sont abordés dans la littérature comme étant les fondements des performances des stratégies d’inclusion financières. À ce titre, ils sont analysés dans différents contextes pour déterminer les méthodologies éprouvées pour leur mise en œuvre. Mots clés : Inclusion financière; Pauvreté; Approche Classification JEL: G20, G21 Type de l’article: Article théorique.

Face à l’acuité de la pauvreté, l’inclusion financière se positionne toujours comme une actualité. Elle ambitionne d’extirper les pauvres du gouffre de l’exclusion et de la marginalisation. L’inclusion financière et la proportion d’individus ou d’organisation accédant à des services financiers d’une gamme variée comme l’épargne, le crédit, les moyes de payement et l’assurance (BM, 2015). Ainsi, l’inclusion financière apparait comme une stratégie universelle de lutte contre la précarité. Son exploration à partir d’une revue de la littérature a permis, dans cet article, de dresser ses contours historiques et théoriques. Avec une ancienneté réelle, à travers le mont-de-piété, l’inclusion financière s’est fortifiée au fil des âges dans ses performances pour se généraliser dans toutes les contrées de la planète. Elle est adoptée ainsi comme une stratégie inclusive de lutte contre la pauvreté par l’octroi de capacités d’accès à une gamme de service financier. Même si sa finalité est de donnée aux pauvres, la possibilité d’intégrer les finances, deux approches aux allures contradictoires se sont côtoyées pour alimenter la réflexion théorique. Les éléments les plus saillants de leur opposition sont la quête de la rationalité et la recherche d’une portée sociale étendue. Toutefois, bien qu’apparemment contradictoire ses approches convergent, tout en se complétant, sur trois déterminants qui fonde les performances de l’inclusion financière. Il s’agit en l’occurrence de l’accessibilité financière, l’utilisation des services financiers et enfin le niveau de qualité. Ces trois déterminants sont abordés dans la littérature comme étant les fondements des performances des stratégies d’inclusion financières. À ce titre, ils sont analysés dans différents contextes pour déterminer les méthodologies éprouvées pour leur mise en œuvre. Mots clés : Inclusion financière ; Pauvreté ; Approche Classification JEL : G20, G21 Type de l’article : Article théorique., In the face of acute poverty, financial inclusion is still a topical issue. It aims to lift the poor out of the abyss of exclusion and marginalization. Financial inclusion refers to the proportion of individuals or organizations accessing a range of financial services such as savings, credit, payment instruments and insurance (WB 2015). Thus, financial inclusion appears to be a universal strategy for fighting poverty. This article explores the historical and theoretical contours of financial inclusion through a review of the literature. With a real antiquity, through the pawnshop, financial inclusion has been strengthened over the years in its performance to become widespread in all parts of the world. It has been adopted as an inclusive strategy to fight poverty by providing access to a range of financial services. Even though its purpose is to give the poor the possibility of integrating finance, two approaches with contradictory appearances have come together to feed the theoretical reflection. The most salient elements of their opposition are the quest for rationality and the search for broad social outreach. However, although seemingly contradictory, these approaches converge, while complementing each other, on three determinants that underpin the performance of financial inclusion. These are affordability, use of financial services and quality. These three determinants are discussed in the literature as the foundations of the performance of financial inclusion strategies. As such, they are analyzed in different contexts to determine proven methodologies for their implementation. Keywords: Financial inclusion; Poverty; Approach Classification JEL: G20, G21 Paper type: Theoretical Research

L’objectif de ce papier est de faire une revue de la littérature en vue d’étayer l’autonomisation des femmes par des études théoriques et empiriques. L’autonomisation des femmes est abordée dans une perspective théorique pour la lutte contre la pauvreté. Les apports revus s’intègrent, dans la problématique de l’habilitation sociale, économique et politique des femmes. À cet effet, des théories et des travaux relatifs à l’autonomisation des femmes ont été explorés. Le concept d’autonomisation des femmes est cerné dans son caractère complexe et multidimensionnel. Sa liaison avec l’équité de genre a permis d’appréhender sa portée sociale, économique et politique. Ainsi les barrières de l’autonomisation des femmes en situation de pauvreté ont été cernées dans leurs différentes dimensions. Enfin, quelques théories de l’autonomisation ont été appréhendées pour fournir un référentiel pour l’empowerment des femmes

We demonstrate a new practical approach for generating multicolour spiral-shaped beams. It makes use of a standard silica optical fibre, combined with a tilted input laser beam. The resulting breaking of the fibre axial symmetry leads to the propagation of a helical beam. The associated output far-field has a spiral shape, independently of the input laser power value. Whereas, with a high-power near-infrared femtosecond laser, a visible supercontinuum spiral emission is generated. With appropriate control of the input laser coupling conditions, the colours of the spiral spatially self-organize in a rainbow distribution. Our method is independent of the laser source wavelength and polarization. Therefore, standard optical fibres may be used for generating spiral beams in many applications, ranging from communications to optical tweezers and quantum optics.

Recent experimental results have reported the observation of beam self-cleaning or, more generally, nonlinear beam reshaping in active multimode fibers. In this work we present a numerical analysis of these processes, by considering the ideal case of a diode-pumped signal amplifier made of a graded-index multimode fiber with uniform Yb doping. Simulations confirm that beam cleaning of the signal may take place even in amplifying fibers, that is the absence of beam energy conservation. Moreover, we show how the local signal intensity maxima, which are periodically generated by the self-imaging process, may influence the population inversion of the doping atoms, and locally saturate the amplifier gain., Comment: 10 pages, 14 figures

Over the last few years, we have experienced a renaissance of nonlinear optics in multimode fibers, driven by both fundamental and applied research. Multimode optical fibers (MMFs) offer a natural environment for investigating multidimensional systems and their complex collective dynamics. Indeed, numerous new nonlinear effects have recently been observed including, for instance, Kerr beam self-cleaning, mode-locking by spatiotemporal filtering, or multimode parametric wave mixing, to name a few [1] . On the other hand, from the application perspective, MMFs are expected to provide interesting novel solutions for high power delivery and increased transmission capacity. Significant work is now in progress to exploit the recently discovered dynamics, and improve the performances of different technologies such as laser endoscopy, nonlinear imaging, and fiber-based laser sources [2] , [3] . In addition, the recent development of advanced measurement techniques, permitting to capture the full spatiotemporal nature of the multimode phenomena has also attracted a strong research interest [4] .

Spatial self-imaging (SSI) consists of the periodic replication of the transverse profile of an optical beam along its propagation. It can be achieved in guided wave systems when all excited modes interfere in phase [1] . Remarkable is the case of graded-index multimode fibers, where the modes propagation constants are equally spaced, and the interference condition becomes trivial, giving rise to a periodic breathing of the field effective area [2] . In the singlemode propagation regime, SSI is by definition impossible. However, bimodal propagation can be attained in a nominal singlemode fiber (SMF-28), when operating in proximity of its cut-off wavelength. The latter imposes the condition for which only the fundamental mode is guided, so that higher-order modes (HOM) vanish over a certain damping distance (typically of about a few centimeters, depending on the wavelength). Therefore, effects associated to the presence of HOM can be present, over propagation lengths shorter than the damping distance.

L’objectif de ce papier est d’analyser l’impact des services financiers de proximité sur l’évolution des capacités réelles d’actions des femmes rurales. Il s’agit de voir comment l’inclusion financière des femmes en tant que stratégie de lutte contre la pauvreté contribue en plus de la création de revenus, à l’évolution d’un potentiel d’actions pour améliorer leur statut social. En s’appuyant sur les modèles d’analyse de l’autonomisation des femmes de Kabeer (2005) et Mayoux (2006), cette recherche a adopté la méthode qualitative pour apprécier l’évolution des capacités réelles d’action des femmes rurales à partir de l’inclusion financière. A cet effet, les représentations, les connaissances, et les pratiques des femmes ont été valorisées à partir d’une enquête de terrain qui a couvert 180 femmes de 36 GEC répartis dans 9 collectivités territoriales de 3 régions du Sénégal. L’étude révèle que l’inclusion financière de proximité garantit aux femmes rurales un accès à l’épargne et au crédit qui sont à un niveau acceptable pour soutenir leur empowerment économique. L’inclusion financière favorise aussi une évolution des capacités réelles d’action et une amélioration du statut social des femmes rurales. L’autonomisation des femmes rurales peut donc s’appréhender avec les capacités réelles d’action produite par l’accès aux services financiers. Toutefois, le potentiel d’action, suscité par l’inclusion financière n’est pas à un niveau capable de favoriser, une déconstruction des relations de genre. Il est donc opportun de prendre en charge les aspirations des femmes rurales avec la réforme des stratégies d’équité de genre afin que les capacités réelles d’action produites par l’inclusion financière puissent favoriser un changement social. En plus, l’accompagnement institutionnel des dispositifs, la formation et l’alphabétisation fonctionnelle pourraient agir positivement sur le potentiel d’actions et le statut social des femmes rurales.

We discuss some recent results illustrating the role of input wave-front shaping, propagation dynamics and output beam diagnostics in order to observe spatial beam cleaning in nonlinear multimode fibers and amplifiers.

We analyzed the nonlinear dynamics of pulsed beam self-cleaning in nonlinear tapered Ytterbium doped and Erbium-Ytterbium codoped graded-index multimode optical fibers, with quasi-uniform doping distribution in the core cross-section. By increasing the net gain when operating in active configuration we observed that the output spatial intensity distribution changed from a speckled into a high-quality and bell-shaped beam. By launching pulses in the normal dispersion regime of the taper, from the wider into the smaller core diameter, we generated a supercontinuum emission between 520 nm and 2600 nm. When the laser pulses were launched into the small core side of the tapered fiber or in the Erbium-Ytterbium fiber, self-cleaning was obtained without any self-phase modulation-induced spectral broadening or frequency conversion.

We observed the generation of a spiral-shaped intensity beams from optical fibers under suitable coupling conditions. In nonlinear regime, we observed rainbow-spiral emission thanks to the generation of supercontinuum in the fiber.

Spatial self-imaging, consisting of the periodic replication of the optical transverse beam profile along the propagation direction, can be achieved in guided wave systems when all excited modes interfere in phase. We exploited material defects photoluminescence for directly visualizing self-imaging in a few-mode, nominal singlemode SMF-28 optical fiber. Visible luminescence was excited by intense femtosecond infrared pulses via multiphoton absorption processes. Our method permits us to determine the mode propagation constants and the cutoff wavelength of transverse fiber modes.

Beam self-imaging of ultrashort pulses in nonlinear graded-index (GRIN) multimode optical fibers is of interest for many applications, including spatiotemporal mode-locking in fiber lasers. We obtained a new analytical description for the nonlinear evolution of a laser beam of arbitrary transverse shape propagating in a GRIN fiber. The longitudinal beam evolution could be directly visualized by means of femtosecond laser pulses, propagating in the anomalous or in the normal dispersion regime, leading to light scattering out of the fiber core via the emission of blue photo-luminescence. As the critical power for self-focusing is approached and even surpassed, a host of previously undisclosed nonlinear effects is revealed, including strong multiphoton absorption by oxygen-deficiency center defects and Germanium inclusions, splitting and shifting of the self-imaging period, filamentation, and conical emission of the guided light bullets. We discovered that nonlinear loss has a profound influence on the process of high-order spatiotemporal soliton fission. The beam energy carried by the fiber is clamped to a fixed value, and nonlinear bullet attractors with suppressed Raman frequency shift and fixed temporal duration are generated, leading to highly efficient frequency conversion of the input near-infrared femtosecond pulses into mid-infrared multimode solitons.

A low intensity light beam emerges from a graded-index, highly multimode optical fibre with a speckled shape, while at higher intensity the Kerr nonlinearity may induce a spontaneous spatial self-cleaning of the beam [1,2]. Here, we reveal that we can generate two self-cleaned beams with a mutual coherence large enough to produce a clear stable fringe pattern at the output of a nonlinear interferometer. The two beams are pumped by the same input laser, yet are self-cleaned into independent multimode fibres. We thus prove that the self-cleaning mechanism preserves the beams' mutual coherence via a noise-free parametric process. While directly related to the initial pump coherence, the emergence of nonlinear spatial coherence is achieved without additional noise, even for self-cleaning obtained on different modes, and in spite of the fibre structural disorder originating from intrinsic imperfections or external perturbations. Our discovery may impact theoretical approaches on wave condensation [3-5], and open new opportunities for coherent beam combining [6-9]., Comment: 8 pages, 3 figures

We experimentally demonstrate a previously unforeseen nonlinear effect in optical fibers: up-conversion luminescence generation excited by multiphoton absorption of femtosecond infrared pulses. We directly estimate the average number of photons involved in the up-conversion process, by varying the wavelength of the pump source. We highlight the role of nonbridging oxygen hole centers and oxygen-deficient center defects and directly compare the intensity of side-scattered luminescence with numerical simulations of pulse propagation.

High energy, ultra-short multimode soliton pulse fission is observed and numerically studied in multimode GRIN fibers, showing complex dynamics bringing to multiple fundamental solitons that do not entirely follow standard single mode soliton perturbation theory predictions.

Beam self-imaging in nonlinear graded-index multimode optical fibers is of interest for many applications, such as implementing a fast saturable absorber mechanism in fiber lasers via multimode interference. We obtain a new exact solution for the nonlinear evolution of first and second order moments of a laser beam of arbitrary transverse shape carried by a graded-index multimode fiber. We have experimentally directly visualized the longitudinal evolution of beam self-imaging by means of femtosecond laser pulse propagation in both the anomalous and the normal dispersion regime of a standard telecom graded-index multimode optical fiber. Light scattering out of the fiber core via visible photo-luminescence emission permits us to directly measure the self-imaging period and the beam dynamics. Spatial shift and splitting of the self-imaging process under the action of self-focusing are also revealed. Funding Agencies|European Research Council (740355); Agence Nationale de la Recherche (ANR-18-CE080016-01); CILAS Company (ArianeGroup); Vetenskapsrådet (2017-05309); Russian Ministry of Science and Education (14.Y26.31.0017)

We experimentally demonstrate spatial beam self-cleaning in an Yb-doped graded-index multimode fiber taper, both in passive and active configurations. The input laser beam at 1064 nm was injected for propagation from the small to the large core side of the taper, with laser diode pumping in a counterdirectional configuration. The Kerr effect permits to obtain high-beam quality amplification with no accompanying frequency conversions. As a result, our nonlinear taper amplifier may provide an important building block for multimode fiber lasers and amplifiers.

We study nonlinear self-imaging dynamics in graded-index multimode optical fibers. Side-scattering of light that accompanies the propagation of intense femtosecond pulses permits us to directly measure the self-imaging period.

The process of high-energy soliton fission is experimentally and numerically investigated in a graded-index multimode fiber. Fission dynamics is analyzed by comparing experimental observations and simulations. A novel nonlinear propagation regime is observed, where solitons produced by the fission have a nearly constant Raman wavelength shift and same pulse width over a wide range of soliton energies.

We demonstrate Kerr self-cleaning of beams in an Ytterbium doped multimode fiber taper with exponentially decreasing nonlinearity, with no accompanying frequency conversion or spectral broadening.

Shedding light on nonlinear loss occurring close to multimode optical fiber damage threshold, we demonstrate that multiple photons are absorbed by material defects and upconverted to shorter wavelength luminescence. An array of blue emitting points results from the spatial self-imaging in graded-index fibers.

International audience; We demonstrate self-induced high beam quality recovery in Er-Yb codoped multimode active fiber with parabolic refractive index profile of the core. Nonlinear beam cleanup is accompanied by Raman and parametric instability sideband generation. Graded-index (GRIN) multimode fibers (MMFs) have become essential tools in the study of spatiotemporal and spectral dynamics of optical waves. These fibers exhibit a periodic self-imaging effect, leading to a periodic refrac-tive index modulation induced by Kerr nonlinearity, and have low modal dispersion, which permits fiber modes to have long interaction lengths. Multimode optical solitons [1], geometrical parametric instabilities (GPI) [2], modulation instability [3], Kerr beam-self-cleaning [4], ultra-wide supercontinuum generation [5, 6], and intermodal four-wave mixing (IFWM) [7, 8] can be cited among the major experimental advances. Nonlinear propagation has been investigated in both the normal and anomalous dispersion regime, by using standard GRIN MMFs, including passive [9] and active [10] multimode tapers. Here we demonstrate the possibility of generating, via Kerr self-cleaning, a high quality beam in a specially designed Erbium-Ytterbium codoped (EYD) MMF with a parabolic index profile. Our experimental results in a passive configuration (i.e., without any pump laser diode) confirm the self-cleaning of a highly multimode beam, leading to record improved beam quality (M 2 = 1.5), accompanied by spectral broadening and different nonlinear frequency conversion processes. The specially designed Erbium-Ytterbium codoped (EYD) GRIN MMF fiber, with uniform doping distribution in the core cross-section, mass concentration of 1.4 % for Yb and 0.6 % for Er, has a core diameter of 65 µm and square cladding with 200 µm side. In order to study nonlinear beam dynamics in a 3 m long EYD GRIN MMF, we used an input Gaussian beam at 1064 nm, with a pulse duration of 500 ps and a repetition rate of 500 Hz. We used a polarizing beam-splitter and two half-wave plates for adjusting peak power and polarization state of the input beam, which was focused into the Er-Yb MMF with a beam diameter of 14 µm at full width of half maximum intensity (FWHMI). The output beam was imaged with a micro-lens on a CCD camera and on the input of an optical spectrum analyzer, to monitor spatial and spectral distributions, respectively. First, by increasing the input coupled peak power (P in) from 0.7 kW up to 56 kW (maximum input peak power), we characterized the output spatial intensity distributions as a function of the power injected into the EYD MMF. Different transverse modes were excited: for low values of input coupled peak power, the spatial output beam pattern was speckled. Increasing of the input peak power leads to a self-organization of the output transverse intensity distribution, leading to spatial beam cleanup above P in =5 kW, that we attribute to Kerr self-cleaning. The insets of Fig. 1a summarize these observations. Next, we studied the power dependence of the output spectrum profile (see Fig. 1b). The output spectral distribution remained almost unchanged as a function of input peak power, well above the appearance of self-cleaning. With an input peak power around 20 kW, large pedestals appear around 1064 nm and 1550 nm (red curve in Fig. 1b). The pedestal close to 1064 nm comes from self-phase modulation, while that around 1550 nm can be related to energy transfer from Yb ions toward Er ions. The intensity of both pedestals increases with input peak power, until stimulated Raman scattering (SRS) leads to a Stokes peak at 1116 nm (corresponding to a-13.4 THz shift) for P in =24 kW (blue curve). Moreover, for P in =29 kW we observed two sidebands at 1041 nm and 1088 nm (green curve), corresponding to a ±6.4 THz shift. The presence of these two sidebands may be attributed to IFWM. At the input peak power of 37 kW, we observed an anti-Stokes sideband at 1016 nm (magenta curve). By gradually increasing the input peak power, significant spectral broadening around 1064 nm and towards longer wavelengths can be observed. Finally, from P in =52.6 kW to P in =56 kW we observed the generation of two additional spectral peaks in the visible region: 739 nm (124 THz) and 624 nm (199 THz).

We experimentally demonstrate the fission of femtosecond pulses in a GRIN standard fiber, leading to high-energy multimode solitons that undergo huge Raman frequency shifts, and exhibit complex multisoliton dynamics.

The dynamics of high-energy Raman solitons in graded-index multimode fibers is both numerically and experimentally investigated. The propagation of high-power pulses produces nonlinear losses, that quench up to 80% of the fiber transmission. In such a regime, several solitons arising from the fission of ultra-short femtosecond pulses manifest unique features: pulse width, Raman self-frequency shift and soliton order remain nearly constant over a broad range of energies.

Recent experiments have shown that nonlinear wave propagation in multimode optical fibers leads to complex spatio-temporal phenomena. In this talk, we introduce new approaches for the control and optimization of nonlinear beam reshaping in the spatial, temporal and spectral dimensions. The first approach applies to spatial beam self-cleaning the technique of transverse wavefront shaping, which permits to launch an optimized input mode combination, that results in the stable generation of a whole nonlinear mode alphabet at the fiber output. The second approach introduces a longitudinal tapering of the core diameter of multimode active and passive fibers, which permits to generate ultra-wideband and high brightness supercontinuum light, featuring high spatial beam quality.

International audience

International audience; We experimentally demonstrate spatial beam self-cleaning in tapered Ytterbium-doped multimodefiber with parabolic index and doping profile in passive and active configurations. We also obtained supercontinuumemission in the range 520 nm-2600 nm.

International audience; We report an experimental observation of staircase pulses generated from an Er:Yb co-doped fiber laser operat-ing in the anomalous dispersion regime. The staircase pulses consist of two distinct square pulses associated withdifferent wavelengths in a dual peak spectrum and they exhibit particular temporal characteristics. To establish atheory behind the experimental results, we simulate numerically the fiber oscillator by using a master equationand taking into consideration the gain inhomogeneities as well as other nonlinear variables.