{"title":"Strong LP11-Mode Splitting in UV Side-Written Tilted Fiber Gratings","authors":"D. Johlen, P. Klose, H. Renner, E. Brinkmeyer","doi":"10.1364/bgppf.1997.bmg.12","DOIUrl":"https://doi.org/10.1364/bgppf.1997.bmg.12","url":null,"abstract":"Dual-mode fiber gratings are promising components for mode converters and reflectionless band filters. In order to be able to use standard telecommunication fibers, which are single-moded at the wavelengths of interest, one can increase the refractive index by UV laser-beam side-writing such that higher modes propagate through the grating region. We show here that UV side-writing is an efficient method to increase the refractive index to allow higher modes to propagate. In addition, the problems of multiple resonant peaks due to weakly broken higher-mode degeneracy [1] is circumvented by breaking the degeneracy such strongly that the resonant peaks are spectrally widely separated.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"24 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128453268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Eggleton, R. Slusher, T. Strasser, C. D. de Sterke
{"title":"High intensity pulse propagation in fiber Bragg gratings","authors":"B. Eggleton, R. Slusher, T. Strasser, C. D. de Sterke","doi":"10.1364/bgppf.1997.bmb.1","DOIUrl":"https://doi.org/10.1364/bgppf.1997.bmb.1","url":null,"abstract":"Recently we reported the first systematic experiments describing high intensity pulse propagation in fiber Bragg gratings [1-3]. These experiments demonstrated nonlinear pulse compression, and pulse shaping, and also demonstrated the generation and propagation of grating solitons [1]. which exist because of the balancing of nonlinearity of the glass and the strong dispersion of the grating [4-6]. Possibly the most striking feature of these solitons is that they can travel at velocities between zero and the speed of light in the medium. Indeed initial experimental, which were performed in uniform (unchirped) gratings, indicated that the solitons propagated at about 75% of the speed of light in the uniform medium. In this paper we review the nonlinear optics of fiber gratings and in particular discuss the experimental realization of grating solitons. We also discuss two extensions of this work: launching of slow grating solitons in apodized fiber gratings; and experimental studies of modulational instabilities (MIs) in Bragg gratings. Finally we mention the possibility of soliton engineering, through the design of nonuniform gratings.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134252824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental and theoretical study of the origin of the second-order nonlinearities induced in thermally poled glasses","authors":"A. Le Calvez, E. Freysz, A. Ducasse","doi":"10.1364/bgppf.1997.pdp5","DOIUrl":"https://doi.org/10.1364/bgppf.1997.pdp5","url":null,"abstract":"To model the poling process, the glass is assimilated to a neutral \"solid electrolyte\". During the poling process, an electric voltage V0 is applied between the cathode and the anode respectively located at x=0 and x=L. The evolution of the ion concentrations is then described by a system of coupled equations containing the equations of diffusion for the different ionic species and Laplace's equation. Since in fused silica, at about 300°C, it is mainly sodium ions, which are mobile, the anions are assumed to be immobile1. According to these approximations and under usual poling conditions (T≈300°C, V0≈3kV), we computed the expression of the potential across the sample during the poling. On Figure 1, we have plotted the potential V(x), the charge distribution ρ(x) and the associated electric field E(x) for a typical silica sample. Since the screening distances di and d2 at the cathode and the anode are much smaller than the sample thickness, the electric field E(x)~V0/d2~108 V/m at the glass interfaces is very high.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134013968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Leconte, W. Xie, M. Douay, P. Bernage, P. Niay, J. Bayon, E. Delevaque, H. Poignant
{"title":"Local Kramers-Kronig analysis of UV induced absorption changes: Dynamics of excess loss induced by exposure to light at 248 nm or 193 nm in Ge:SiO2 preforms.","authors":"B. Leconte, W. Xie, M. Douay, P. Bernage, P. Niay, J. Bayon, E. Delevaque, H. Poignant","doi":"10.1364/bgppf.1997.jmf.2","DOIUrl":"https://doi.org/10.1364/bgppf.1997.jmf.2","url":null,"abstract":"It is well known that exposure of a germanosilicate glass to light at 248 nm or 193 nm leads to a permanent change in the refractive index and in the absorption spectra at wavelength shorter than 350 nm. The changes in absorption spectra are assumed to result either from the creation of point defects (color center model)1,2 and/or from light induced structure changes in the glass (densification model)3,4. A Kramers-Kronig (KK) transformation of the changes in absorption enables one to determine the related changes in refractive index which in turn can be compared with those measured at the time of a grating inscription. However using this process is rather tricky since ideally the comparison requires that when writing a grating within a fiber, one measures the UV induced excess loss spectrum at each exposure time and at each place along the grating wavevector on the spectral range within which the absorption changes are observed. As the above mentioned procedure cannot be strictly followed, we suggested a simplified method5 for performing the KK analysis. We use this method to compare the index changes which can be ascribed to absorption changes occurring in the spectral range (220 - 350 nm) at the time of a grating inscription through exposure of a germanosilicate fiber either to a fringe pattern at 193 nm or 248 nm.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133046762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of an optical frequency-hop encoder with strain-tuned Bragg gratings","authors":"H. Fathallah, S. Larochelle, L. Rusch","doi":"10.1364/bgppf.1997.bmg.5","DOIUrl":"https://doi.org/10.1364/bgppf.1997.bmg.5","url":null,"abstract":"In optical communication systems, fiber gratings have been used to perform chromatic dispersion compensation, gain equalization, pulse compression, soliton pulse shaping, add/drop switching and channel filtering for wavelength division multiplexing (WDM) systems [1,2]. Recently Chen et al. studied a multiple grating structure that could be used to achieve spectral slicing in WDM and CDMA systems [3]. In this paper we propose a tunable multiple-grating fiber for frequency-hop encoding-decoding operations. To our knowledge, this is the first proposal for frequency-hop code division multiple access (FH-CDMA) in optical fiber local area networks.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"218 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125630057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of photosensitivity in planar silica-on-silicon optical waveguides","authors":"Y. Hibino","doi":"10.1364/bgppf.1997.btub.1","DOIUrl":"https://doi.org/10.1364/bgppf.1997.btub.1","url":null,"abstract":"Planar lightwave circuit (PLC) devices such as splitters, Mach-Zehnder interferometers and arrayed-waveguide grating (AWG) multiplexers, have been developed using GeO2-SiO2 waveguides on Si substrates. Such devices typically have low propagation and fiber-connection losses. Advanced optical communication systems, such as wavelength division multiplexing (WDM) systems, optical switching systems, and optical access networks[1] uses PLC devices. These silica-based planar waveguides are photosensitive[2]. This property can be used to make new types of PLC devices. For instance, photo-induced refractive index changes have been used for trimming the spectral response in the PLCs and forming Bragg gratings in the same way as used for optical fibers [3].","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"57 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113939387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Periodic structures in photo-thermo-refractive glasses induced by homogeneous UV irradiation","authors":"L. Glebov, V. Smirnov","doi":"10.1364/bgppf.1997.jsue.15","DOIUrl":"https://doi.org/10.1364/bgppf.1997.jsue.15","url":null,"abstract":"Samples of photo-thermo-refractive glasses were exposed to a homogeneous collimated beam of a He-Cd laser at 325 nm. A refractive index change is observed in the exposed glass upon thermodevelopment due to photoinduced crystallization. A periodic structure was observed inside this exposed area by optical microscopy. This structure is a system of parallel continuous aligned filaments having widths of ten's of microns oriented along the direction of light propagation. Variation of incident light polarization direction does not effect the resulting structure.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117114473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Jouanno, D. Zauner, M. Svalgaard, Morten Rode Kristensen
{"title":"Low Crosstalk Optical Add-Drop Multiplexer based on a Planar Silica-on-Silicon Mach-Zehnder Interferometer with UV-induced Bragg Gratings and UV-Trimming.","authors":"J. Jouanno, D. Zauner, M. Svalgaard, Morten Rode Kristensen","doi":"10.1364/bgppf.1997.btua.3","DOIUrl":"https://doi.org/10.1364/bgppf.1997.btua.3","url":null,"abstract":"Optical Add-Drop Multiplexers (OADM) are key-components of multi-wavelength optical networks. Several techniques and designs may be used in order to achieve this function [1]. UV-induced Bragg gratings are of great interest since they enable construction of compact devices, and when written in the arms of a planar Mach-Zehnder interferometer they realise an OADM device with potentially low crosstalk. Moreover this device drops one channel without altering the other ones enabling cascading of several OADM's. Silica-on-Silicon planar OADM devices based on Mach-Zehnder interferometers have already been reported by other groups [2-5] but they were all limited by a low grating strength leading to a ratio between the -30 dB bandwidth in transmission and the -20 dB bandwidth in reflection, the so-called Bandwidth Utilisation parameter (BWU) [6], equal to zero and therefore a high intra-channel crosstalk. We present in this paper a planar OADM with a positive BWU obtained by writing strong gratings in waveguides [7].","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115387126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Espindola, R. Atkins, N. P. Wang, D. Simoff, M. Paczkowski, R. Windeler, D. Brownlow, D. Shenk, P. A. Glodis, T. Strasser, J. Demarco, P. J. Chandonnet
{"title":"40 dB Fiber Bragg Grating Written Through The Fiber Coating at 257 nm","authors":"R. Espindola, R. Atkins, N. P. Wang, D. Simoff, M. Paczkowski, R. Windeler, D. Brownlow, D. Shenk, P. A. Glodis, T. Strasser, J. Demarco, P. J. Chandonnet","doi":"10.1364/bgppf.1997.pdp2","DOIUrl":"https://doi.org/10.1364/bgppf.1997.pdp2","url":null,"abstract":"The writing of fiber Bragg gratings through the coating has important implications for the mass production of these devices. For instance, the time-consuming steps of stripping and recoating of the grating (potentially leading to fiber strength degradation), can be completely eliminated resulting in a simpler, more efficient and lower cost fabrication process. In the first demonstration of writing Bragg gratings through the coating, up to ~3 dB Bragg gratings were written through a UV-transparent acrylate-based 25 μm thick coating at 257 nm [1]. Subsequently, other researchers demonstrated a ~1 dB fiber Bragg grating written through a standard coating using 334 nm light [2]. Because the absorption band at 334 nm is much weaker than at 244 nm, these gratings required a very high germanium concentration (~20 mol%) and the addition of boron as a codopant to increase the photosensitivity of the fiber. The high level of germanium makes it difficult to achieve low-loss splices to standard communications grade fiber. Here we report for the first time highly reflective (99.99% Reflectivity, -40 dB transmission) Bragg gratings written through a novel polymer coating using a photosensitive germanium-doped fiber with 5 mole% germania.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125391458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Dianov, M. V. Grekov, I. Bufetov, S. A. Vasiliev, O. Medvedkov, G. Ivanov, A. V. Belov, V. Plotnichenko, V. Koltashev, A. Prokhorov
{"title":"Novel High Power 1.24 μm And 1.48 μm Raman Lasers Based On Phosphosilicate Fiber","authors":"E. Dianov, M. V. Grekov, I. Bufetov, S. A. Vasiliev, O. Medvedkov, G. Ivanov, A. V. Belov, V. Plotnichenko, V. Koltashev, A. Prokhorov","doi":"10.1364/bgppf.1997.bmc.2","DOIUrl":"https://doi.org/10.1364/bgppf.1997.bmc.2","url":null,"abstract":"At present cascaded Raman fiber lasers pumped by Nd or Yb fiber lasers have found wide application. The growing interest in such lasers has been caused by the possibility to generate the high power CW radiation at the wavelengths of 1.24 and 1.48 μm.","PeriodicalId":182420,"journal":{"name":"Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128185559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}