Kobyakov A.,Corning Inc. |
Sauer M.,Corning Inc. |
Chowdhury D.,Corning European Technology Center
Advances in Optics and Photonics | Year: 2010
We present a detailed overview of stimulated Brillouin scattering (SBS) in single-mode optical fibers. The review is divided into two parts. In the first part, we discuss the fundamentals of SBS.A particular emphasis is given to analytical calculation of the backreflected power and SBS threshold (SBST) in optical fibers with various index profiles. For this, we consider acousto-optic interaction in the guiding geometry and derive the modal overlap integral, which describes the dependence of the Brillouin gain on the refractive index profile of the optical fiber. We analyze Stokes backreflected power initiated by thermal phonons, compare values of the SBST calculated from different approximations, and discuss the SBST dependence on the fiber length.We also review an analytical approach to calculate the gain of Brillouin fiber amplifiers (BFAs) in the regime of pump depletion. In the high-gain regime, fiber loss is a nonnegligible effect and needs to be accounted for along with the pump depletion.We provide an accurate analytic expression for the BFA gain and show results of experimental validation. Finally, we review methods to suppress SBS including index-controlled acoustic guiding or segmented fiber links. The second part of the review deals with recent advances in fiber-optic applications where SBS is a relevant effect. In particular, we discuss the impact of SBS on the radio-overfiber technology, enhancement of the SBS efficiency in Raman-pumped fibers, slow light due to SBS and SBS-based optical delay lines, Brillouin fiber-optic sensors, and SBS mitigation in high-power fiber lasers, as well as SBS in multimode and microstructured fibers. A detailed derivation of evolutional equations in the guided wave geometry as well as key physical relations are given in appendices. © 2009 Optical Society of America.
Gordon I.,IMEC |
Vallon S.,Corning European Technology Center |
Mayolet A.,Corning Inc. |
Beaucarne G.,IMEC |
Solar Energy Materials and Solar Cells | Year: 2010
Solar modules made from thin-film crystalline-silicon layers of high quality on glass substrates could lower the price of photovoltaic electricity substantially. One way to create crystalline-silicon thin films on non-silicon substrates is to use the so-called "seed layer approach", in which a thin crystalline-silicon seed layer is first created, followed by epitaxial thickening of this seed layer. In this paper, we present the first solar cell results obtained on 10-μm-thick monocrystalline-silicon (mono-Si) layers obtained by a seed layer approach on transparent glass-ceramic substrates. The seed layers were made using implant-induced separation and anodic bonding. These layers were then epitaxially thickened by thermal CVD. Simple solar cell structures without integrated light trapping features showed efficiencies of up to 7.5%. Compared to polycrystalline-silicon layers made by aluminum-induced crystallization of amorphous silicon and thermal CVD, the mono-Si layers have a much higher bulk diffusion lifetime. © 2009 Elsevier B.V. All rights reserved.
Hervy M.,Corning European Technology Center
Journal of Adhesion Science and Technology | Year: 2010
The mechanical balance maintained between the cell and its environment forms the basis of tissue formation, cohesion and homeostasis. Cells are able to sense the mechanical characteristics of the extracellular medium and to modulate their function accordingly. Furthermore, cells are able to modulate the mechanical properties of their environment in response to intracellular signals. In this article we review recent papers describing the regulators and signaling pathways involved in these processes. We describe how the adhesion sites of the cell to the Extra Cellular Matrix are of primary importance in sensing force and how the actin network via actomyosin contractility and the associated Rho-family dependent regulatory paths also play a key role in mechanotransduction. We then focus on the different types of cellular responses to forces: modulation of adhesion, shape, migration properties, proliferation rate or regulation of differentiation. Cellular response can also be communicated to neighboring cells and be integrated to modulate processes such as development and can lead to diseases if misregulated. © 2010 Koninklijke Brill NV, Leiden.
Overend M.,University of Cambridge |
Butchart C.,University of Cambridge |
Lambert H.,Eckersley OCallaghan Engineers |
Prassas M.,Corning European Technology Center
Composite Structures | Year: 2014
Conventional laminated glass has a relatively low post-fracture strength and stiffness, which imposes several constraints on the structural use of glass in buildings. This paper proposes a new generation of laminated hybrid-glass units, built-up from plies of chemically strengthened glass, conventional polymer interlayers and heat treated/annealed glass, that aim to outperform conventional laminated glass units. The paper describes the experimental investigations on the novel laminated hybrid-glass units subjected to quasi-static out-of-plane loads and presents the corresponding analytical models developed to characterise the load-deflection response of the units, both in the unfractured and post-fractured states. The experimental data shows that laminated hybrid-glass units can achieve significant post-fracture stiffness and their post-fracture strength can equal or exceed the strength at first fracture. The analytical models are successfully validated and the equivalent shear modulus approach developed in this paper facilitates future numerical analysis and optimisation of these units. © 2013 Elsevier Ltd.
Tuzun O.,French National Center for Scientific Research |
Tuzun O.,Muǧla University |
Slaoui A.,French National Center for Scientific Research |
Maurice C.,Ecole Nationale Superieure des Mines de Saint - Etienne CMP |
Vallon S.,Corning European Technology Center
Applied Physics A: Materials Science and Processing | Year: 2010
In this work, we present extended structural properties of poly-Si thin films fabricated by aluminium-induced crystallization (AIC) of amorphous silicon (a-Si) on hightemperature glass-ceramic substrates. The silicon nucleation kinetics on glass-ceramic substrates was investigated by optical microscopy. The crystalline quality of the films was studied by micro-Raman spectroscopy as a function of exchange annealing conditions. By means of electron backscattering diffraction (EBSD), we have analyzed the effect of thermal annealing on silicon grain size and its distribution, intra- and inter-grains defects, and on the grains preferential crystallographic orientation. The optimal thermal annealing condition, allowing 100% crystallized polysilicon large grains with an average grain size of 26 μm and (100) oriented, acquired a thermal budget of 475°C and 8 h. © Springer-Verlag 2009.
Horn C.,Corning European Technology Center |
Cerato-Noyerie C.,Corning European Technology Center
Journal of Flow Chemistry | Year: 2014
A convenient and simple PdCl2-based hydrogenation catalyst has been developed. The liquid, air, and moisture stable precursor is pumped into the reactor where it is temporarily immobilized and reduced on the channel surface into Pd(0), providing a constant high activity for hydrogenation reaction. The catalyst is leached with time, avoiding any kind of clogging problems during long time runs. © 2014 Akadémiai Kiadó.
Rossi E.,Corning European Technology Center |
Woehl P.,University of Padua |
Maggini M.,Corning European Technology Center
Organic Process Research and Development | Year: 2012
Diazomethane is a valuable derivatizing agent but very difficult to handle for large-scale chemical transformations. We report here the base-induced decomposition of N-methyl-N-nitrosourea under continuous-flow conditions that enables the production up to 19 mol d -1 of diazomethane, at a total flow rate of 53 mL min -1. © 2011 American Chemical Society.
PubMed | Corning Scientific Center, Corning European Technology Center and Saint Petersburg State University of Information Technologies, Mechanics and Optics
Type: Journal Article | Journal: Physical review. E | Year: 2016
Ultrasonic near-field levitation allows for contactless support and transportation of an object over vibrating surface. We developed an accurate model predicting pressure distribution in the gap between the surface and levitating object. The formulation covers a wide range of the air flow regimes: from viscous squeezed flow dominating in small gap to acoustic wave propagation in larger gap. The paper explains derivation of the governing equations from the basic fluid dynamics. The nonreflective boundary conditions were developed to properly define air flow at the outlet. Comparing to direct computational fluid dynamics modeling our approach allows achieving good accuracy while keeping the computation cost low. Using the model we studied the levitation force as a function of gap distance. It was shown that there are three distinguished flow regimes: purely viscous, viscoacoustic, and acoustic. The regimes are defined by the balance of viscous and inertial forces. In the viscous regime the pressure in the gap is close to uniform while in the intermediate viscoacoustic and the acoustic regimes the pressure profile is wavy. The model was validated by a dedicated levitation experiment and compared to similar published results.