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In this paper Tm-doped tellurite glasses (75TeO 2 –20ZnO–5 Na 2 O, mol%) were studied and sensitization with Yb 3+ as co-dopant was carried out in order to assess its influence on the emission properties and improve pump efficiency and wavelength emission range. Emission spectra and lifetime measurements were obtained by pumping either at 785 nm or 980 nm, thus exploiting the Yb–Tm energy transfer mechanism. Doping levels of Yb from below 1 to up 5 mol% were investigated in order to evaluate the effectiveness of energy transfer process and glasses containing an overall content of 9 mol% rare earth ions were proved to be successfully fabricated. All glasses were fully characterized from a material and spectroscopic point of view. Tellurite glasses with 4 and 1 mol% of Tm 3+ and Yb 3+ ions respectively were found to show a good compromise between emission efficiency and lifetime decay values. A quenching concentration of Yb 3+ ions up to 14 mol% was also defined for this type of glass system.

Silver nanocluster–silica composite coatings have been deposited by radio frequency (RF) co-sputtering on silica substrates. UV–visible absorption and X-ray diffraction spectra of the as deposited and heated samples revealed metal silver nanoclusters of different size, depending on the annealing treatment. The antibacterial activity of several as deposited and annealed samples has been verified in accordance to National Committee for Clinical Laboratory Standards (NCCLS). The antibacterial activity of these coatings was detected up to 450 °C.

This work describes the design of three new glass and glass ceramic compositions to join the ceramic electrolyte (YSZ wafer) to the metallic interconnect (Crofer22APU) in planar SOFC stacks. The designed sealants are low-sodium, barium free and boron-oxide free silica-based glasses. The sealing process was optimized for the most promising composition and joined Crofer22APU/glass–ceramic sealant/YSZ samples were morphologically characterized and tested for 300 h in humidified hydrogen atmosphere at the fuel cell operating temperature of 800 °C. The study showed that the use of the glass–ceramic was successful in joining the YSZ ceramic electrolyte to the Crofer22APU metallic interconnect and in preventing severe corrosion effects at the Crofer22APU/glass–ceramic interface after static treatments in humidified hydrogen at 800 °C for 300 h.

We performed extensive spectroscopy of tellurite glasses doped with high concentration of Tm ions for laser emission at around 2 micron wavelength. The aim of the work is to develop a glass suitable for single-frequency fiber laser. In fact such a kind of laser require the use of short cavity length and therefore high gain per unit length medium. Tellurite glasses allows high-doping concentration and are therefore an excellent candidate. In these paper we review our recent results. In particular we address the optical and thermo-mechanical properties of several tellurite glasses (75mol%Te02.20mol%ZnO. 5mol%Na2O) with Tm3+ doping up to 111, 564 ppm.

Surface treatment on glass before thermal assisted direct bonding (TADB) is an issue for lab-on chip fabrication. Surface cleaning for obtaining good quality TADB on soda-lime glass are studied and tested in this paper. The optimized cleaning solution for soda lime glass samples is NH4OH–H2O2–H2O (0.5:1:5 volume ratio) and it can be considered as the optimised solution for cleaning soda-lime glasses by this solution, as a result of a trade-off between cleaning efficiency and surface etching. The surface quality before and after cleaning is evaluated by optical microscopy, profilometry and atomic force microscopy. TADB between the cleaned samples is carried out and the bonding strength measured. The tensile strength of optimized samples after TADB was found to be higher than 15 MPa.

Thin film (40–600 nm) yttria-stabilized zirconia (YSZ) electrolytes for solid oxide fuel cells (SOFC) were deposited on NiO-YSZ anodes and fused silica substrates by RF sputtering, using low applied power without the use of post deposition annealing heat treatment. YSZ film showed a nanocrystalline structure and consisted of the Zr.85Y.15O1.93 (fcc) phase. The film was dense and the YSZ/anode interface was continuous and crack free. According to preliminary in-plane conductivity measurements (temperature range 550–750 °C) on the YSZ film, the activation energy for ionic conduction was found to be 1.18 ± 0.01 eV.

The interaction of dioxygen with slightly acidic X—H molecules at the MgO surface causes oxidation reactions typically involving O–2 as intermediate. EPR-detectable species are observed only on samples outgassed at 1070 K, together with small amounts of by-products, revealed by IR spectroscopy. This latter reaction and the overall oxidation are part of the same network. The first step is the dissociative adsorption of X—H (X—H + O2–(s)→ X–+ OH–), the second is intermolecular electron transfer (X–+ O2→ X˙+ O–2). On MgO samples outgassed at low temperatures, all O–2 species are unstable and react quantitatively with the X˙ radicals to yield oxidation products. In addition, on MgO outgassed at 1070 K strongly coordinatively unsaturated cations act as traps for O–2 species which become EPR visible. The accompanying X˙ radical species reacts with dioxygen to yield a second O–2 and an oxygenated species XO– responsible for the IR signals. The nature of the XO– species is discussed in the cases of propene, benzene and toluene; further reactions of O–2 and the molecular properties of X—H controlling superoxide formation are also discussed.

The development of stable single frequency fiber laser requires the use of short cavity length and therefore high gain per unit length medium. Tellurite glasses possess the suitable properties to realize such a device that would operate in the 2µm wavelength region. Amongst those properties are low phonon energy and high rare earth ion solubility. The optical and thermo-mechanical properties of a series of tellurite glasses (75mol%TeO 2 .20mol%ZnO-5mol%Na 2 O) highly doped with Tm3+ ions (up to 111,564 ppm) are presented and discussed. The results presented suggest an optimum concentration in Tm3+ of about 60,000 ppm to be used as fiber core material. An adequate glass composition for fiber cladding is also proposed.

In this paper, optical properties of 75TeO 2 –20ZnO–5Na 2 O host glass doped with concentration of Tm 3+ up to 10 %mol were studied in order to assess the most suitable rare earth content for short cavity fiber lasers. Raman spectroscopy revealed a change in the glass structure while increasing Tm 3+ content, similar to the well known addition of alkali ions in a glass. Influence of the fabrication process on the OH − content was determined by FTIR measurements. Refractive index of Tm 3+ doped tellurite glasses was measured at five different wavelengths ranging from 533 nm to 1533 nm. Lifetime and emission spectra measurements of the Tm 3+ doped tellurite glasses are reported.

Glasses based on (85 − x)TeO2–xZnF2–12PbO–3Nb2O5 (x = 0–40) system have been studied for the first time for fabricating mid-infrared optical fiber lasers. The thermal and optical properties including UV–Vis, Raman as well as FTIR spectra are reported. It is demonstrated that increasing the ZnF2 concentration to 30 mol% significantly increased the thermal stability of the glass. Adding ZnF2 also reduced the hydroxyl (OH) content of the glass resulting in lower optical absorption in the mid-infrared region, which is crucial for infrared laser applications. The glass absorption cut-off edge near 400 nm blue-shifts with increasing ZnF2 addition. Raman spectra show a depolymerization of the glass network with increasing transformation of TeO3+1 to TeO3 structures.

Future linear accelerators, as CLIC (Compact LInear Collider), are extremely demanding in terms of material properties. Traditionally accelerating structure is made of brazed OFE copper parts. For the high conducting regions submitted to mechanical fatigue, CuZr would represent an improved selection than pure copper while for regions where the highest electric field is applied a refractory metal, i.e. Mo, could result in a better performance. The feasibility of joining such materials, namely CuZr (UNS C15000) and pure Mo has been investigated. The joining method developed and investigated here consists in a vacuum brazing process exploiting a Cu-based brazing filler applied under appropriate vacuum conditions. Apparent shear strength (adapted from ASTM B898) on the joined samples was about 200 MPa.

TeO 2 -ZnF 2 -PbO-Nb 2 O 5 based fluorotellurite glasses were synthesized and studied for the first time for laser applications. The property characterizations including XRD and thermal analysis as well as optical properties measurement were performed. It is demonstrated that this fluorotellurite system has good glass formation ability; and increasing the ZnF 2 concentration to 30 mol% can significantly increase the thermal stability of the glass. Adding ZnF 2 also reduced remarkably the hydroxyl (OH) concentration of the glass resulting in lower optical absorption in the infrared region, which is crucial for infrared laser applications. In addition, the glass absorption cut-off edge near 400 nm blue-shifted with increasing ZnF 2 addition.

In this paper we describe fabrication and characterization of rare-earth-doped active tellurite glasses to be used as active laser media for fiber lasers emitting in the 2 μm region. The base composition is (mol%): 75TeO2–20ZnO–5Na2O with different concentrations of Tm3+, Yb3+ and Ho3+ as dopants or co-dopants. Optical properties of doped glasses were studied and pumping at 800 nm and at 980 nm were tested in order to compare the efficiency of two pumping mechanisms. Optical characterization carried out on glasses containing only Tm3+ ions indicated the optimum concentration of Tm2O3 in terms of emission efficiency as 1 wt%. The addition of 5 wt% of Yb2O3 to Tm3+-doped glasses led to the best results in terms of intensity of fluorescence emission and of lifetime values. Yb and Ho co-doped Tm-tellurite glass was measured in emission.

Experimental method for evaluation of residual stress distribution in carbon fiber reinforced car­bon composite jointed to copper is presented. Pulse electric current passed through composite-to-copper joint essentially reduces the level of residual stresses. Представлено експериментальну методику щодо оцінки розподілу залишко­ вих напружень у з’єднанні композита (вуглець, зміцнений вуглецевими волокнами) з міддю. Установлено, що імпульс електричного струму, що пропущений через з’єднання композит-мідь, суттєво зменшує рівень залиш­ кових напружень. Представлена экспериментальная методика оценки распределения остаточных напряжений в соединении композита (углерод, упрочненный углеродными волокнами) с медью. Уста­новлено, что импульс электрического тока, пропущенный через соединение композит-медь, существенно снижает уровень остаточных напряжений.

This paper describes the design and development of a composite seal for SOFC to produce a hermetic joint between the ceramic and metallic components of the SOFC stacks. The composite seal was designed to be chemical compatible with the ceramic electrolyte (YSZ) and the interconnect (AISI 430), to have suitable thermo-mechanical properties ( T g , thermal expansion coefficient, TEC), and good wettability with them. The reinforcing phase (alumina) was chosen to increase the seal viscosity at the SOFC working temperature (about 800 °C), to improve the thermal shock resistance of the seal and to match the thermal expansion coefficient of the components to be joined. The seal was morphological and thermo-mechanical characterized by scanning electron microscopy, SEM, energy dispersive spectroscopy, EDS, thermo-mechanical analysis, TMA, X-ray diffraction, XRD and differential thermal analysis, DTA. The joining process between YSZ and AISI 430 was optimized taking into account that the maximum process temperature should be around 1000 °C. Joined samples were preliminary submitted to H 2 –3% H 2 O atmosphere exposure at 800 °C for 200 h.

This work describes the design and development of a glass–ceramic seal to produce a hermetic joint between the ceramic electrolyte and the metallic interconnect of planar SOFC stacks. The glass–ceramic composition was designed considering the chemical compatibility with the ceramic electrolyte (yttria stabilized zirconia) and the oxidation resistant metal alloy interconnect (Crofer 22 APU), the thermo-mechanical properties (characteristic temperatures, thermal expansion coefficient), and the wettability on the substrates. The designed glass–ceramic seal is a barium-free silica-based glass, which partially crystallizes during the heat treatment after being deposited on Crofer 22 APU substrate by slurry coating or by electrophoretic deposition. The sealing process of the glass–ceramic was optimized, also taking into account that the maximum processing temperature should be lower that 950 °C (upper limit for the metallic interconnect) and the maximum heating rate of about 5 °C/min (limit for ceramic components). The joined ceramic/seal/metal samples were morphologically characterized and preliminary tested for 400 h in air atmosphere at the fuel cell operating temperature of 800 °C. Thermal ageing in air caused a Cr-diffusion from Crofer 22 APU alloy to the seal only when the alloy was used in the as-received condition. The preoxidised one did not diffuse Cr ions through the seal under the same ageing conditions.

In this paper the fabrication, characterization, and thermal assisted bonding of two photosensitive silicate glasses is presented, as part of a wider process aiming to obtain a planar waveguide lossless splitter for telecom applications. Two glass compositions are investigated: an Er–Yb doped silicate glass, which amplifies the signals when pumped at 980 μm and a matchable passive glass, which is designed to host the waveguide splitter. The two parts were bonded successfully using direct bonding technique at 605 ± 20 °C for 240 min under a pressure of 28 kPa. Vickers hardness measurements were made on the bulk glasses and at the bonded interface, which showed no cracks propagating along the interface.

Surface devitrification of fluorozirconate glasses has a dominant role in preform drawing and highly depends on environmental conditions. The effects of different atmospheres (N 2 , SF 6 , CF 4 , CHF 3 , CHCIF 2 , CHCl 2 F, CCl 2 F 2 , CBrF 3 , C 2 F 6 , C 2 ClF 5 , C 2 Cl 2 F 4 , C 3 F 8 , air) and different materials (platinum, gold, graphite, Teflon ® PTFE, aluminum) normally used in glass processing were analysed. The devitrification phenomenon, occuring on the surface and into the bulk after sample reheating at drawing temperature, was checked by several analysis techniques and the kinetic parameters were calculated by DSC analysis to evaluate effects induced by different materials. Surface devitrification of glasses treated under CF 4 atmosphere is less evident than for samples treated under other gases. Moreover it was found that platinum should be avoided for glass processing equipments, because of its tendency to induce crystallization.

Different processes for the preparation of fluorozirconate glasses (ZBLAN) have been investigated by infrared spectroscopy (IR) and x-ray diffraction (XRD) on fluoride powders, during the reaction. Glasses have been prepared with 20-10-5-0 (% weight) ammonium bifluoride (NH4F·HF) or with nitrogen trifluoride (NF3) as fluorinating agent. In order to improve the quality of the glasses, small percentages (about 5%) of NH4F·HF are a good compromise between fluorination and hydration of starting products; NF3 is very effective during the fluorination step of the preparation: our electron spin resonance measurements (ESR) on these last glasses after γ-irradiation (20 Mrad), do not detect any O2 signal.

Bottom ashes from a north Italian municipal solid waste incinerator (MSWI) were vitrified at 1450 °C without adding any vitrifying agent, then ground and sieved to different granulometry (ranging from 50 μm to 20 mm), and used as filler, sand, or aggregate for concrete. Samples were characterized via slump tests (UNI 9418), alkali-silica reactivity (UNI 8520/22 and ASTM C 298), and compression strength tests (UNI 6132, 6132/72, 6686/72), and compared to reference samples obtained without vitrified bottom ashes (VBA). Our results show that vitrified bottom ashes are unsuitable as a sand substitute; however, concrete containing up to 20 wt.% of VBA filler used as a substitute for cement and up to 75 vol.% of VBA as a substitute for natural aggregate retains the same mechanical properties as reference samples. Alkali-silica or other detrimental reactions were not observed in VBA-containing concrete samples after a period of two years. The results of this work demonstrate that vitrified bottom ashes from MSWI can be used instead of natural aggregates in mortar and concrete production.

Bragg gratings have been written in an optical fibre with a core made of ternary SiO2:SnO2:Na2O glass and a SiO2 cladding. The presence of Na2O allows for higher concentrations of SnO2 which is believed to be responsible for the photorefractive response of this composition. In these preliminary experiments significant refractive index modulations, up to 6.2x10-4, have been achieved using a 248nm excimer laser and a phase mask to write gratings for reflectivity at around 1.5µm. The induced refractive index changes show enhanced temperature stability and there is no sign of any erasure up to temperatures exceeding 600°C.

The topic of this review is a summary of the photonics research currently performed at the Material Science and Chemical Engineering Department at Politecnico di Torino, with an emphasis on novel tellurite glasses and nanocluster doped silica for photonics. The fabrication and characterization of novel tellurite glasses and their optical fibers, with the aim of obtaining laser sources operating in the near infrared, will be reviewed. Doping with Tm, Yb and Ho have been investigated and different pumping schemes are evaluated in order to optimize laser performance. Nanocluster doped glasses, which are of great interest for nonlinear applications in telecommunications as well as for different types of plasmonic sensors, will also be discussed. Specifically, the fabrication and characterization of nano-metal glass composites manufacturing by RF sputtering.

In this paper Tm-doped tellurite glasses (75TeO 2 -20ZnO-5 Na 2 O, mol%) were prepared and characterized, and codoping with Yb was investigated in order to improve pump efficiency and wavelength emission range. Emission spectra and lifetime measurements were obtained by pumping Tm-doped tellurite glasses at 800 nm and Yb-Tm co-doped tellurite glasses at 980 nm, thus exploiting the Yb-Tm energy transfer mechanism. Highly Yb-doped Tm-tellurite glasses were investigated (Yb 2 O 3 concentrations up to 5 wt%) and an increase in 3 F 4 lifetime with Yb 2 O 3 concentrations higher than 3% was observed. This showed that high amounts of Yb do not affect lifetime of the metastable state, thus allowing investigation of lasers in this range of doping concentrations.

Commercially pure titanium is among the most biocompatible metals available for dental uses: it combines good mechanical properties with high corrosion resistance in simulated body fluids. However, titanium casting shows some problems mainly related to its high melting temperature and chemical reactivity with oxygen at T > 600 °C; as a consequence, molten titanium reacts with crucibles and mould components during casting. In this research, new Y 2 O 3 -based slurry was used to produce yttria coated mullitic crucibles and wax pattern coatings for induction melting of titanium; furthermore, a detailed comparison among 4 different investment materials (one silica-based, one ZrSiO 4 -based and two MgO-based) was performed. The titanium surface after casting was investigated with optical and electron microscopy (SEM) and energy dispersion spectroscopy (EDS). A reaction zone was observed on Ti when cast in an uncoated crucible, while a clean, pure Ti surface was obtained by using yttria coated crucibles and yttria coated wax patterns before investing with silica-based and zircon-based investment.

The divertor design of the ITER fusion machine comprises the joint between CFC composites and the copper alloy heat sink. The main problem of the CFC-Cu joint manufacturing is the large thermal expansion mismatch of the components and the very high contact angle of molten copper on carbon substrates. The aim of this work is to develop a new technique to join CFC composite to pure copper. In order to increase the wettability of CFC by molten copper, the composite surface was modified by direct reaction with group VI transition metals which form a carbide layer and allow a large reduction of the contact angle. A morphological analysis and the mechanical and thermal shock tests were performed to characterize the CFC-Cu joined samples.

In this paper the preparation and characterization of nanostructured materials via co-sputtering of SiO2 and silver followed by a suitable heat-treatment for size and fill factor control is described. Transmission electron microscopy (TEM), X-ray and UV–Vis spectroscopy have been carried out to evaluate the cluster size and the optical properties of the composite films, which are a direct consequence of quantum and dielectric confinement effect. Computer simulations have been performed in order to compare the experimental data with theory. Tuning of cluster size and optical properties of the composite thin films is demonstrated by varying deposition conditions and following heat-treatments.

The diffraction efficiency of gratings written in ternary SnO2:SiO2:Na2O bulk glasses rises dramatically with time after the occultation of the cw 244nm light used to write the thick hologram. This self-induced behavior lasts for several hours and ultimately leads to refractive index changes as high as 3 10-3.

The bottom ashes coming from two different municipal solid waste incinerators were vitrified at 1400 °C. The obtained glass, mixed with other wastes coming from metallurgical and mineral industrial wastes, was used as raw material for the production of glass–ceramic tiles. Two different mixtures were used for the tile production: (a) glass from bottom ashes plus corundum-based waste from an aluminum foundry and (b) glass from bottom ashes plus kaolin-based waste from the kaolin ore extraction process. The tiles were prepared in air by a low-cost, low-temperature pressureless sintering process and were morphologically and mechanically characterized. The sintered materials were found to be good candidates for building applications (tiles, bricks, etc.), i.e. they showed bending strengths up to about 60 MPa and Young modulus up to about 53 GPa.

A protective coating for SiC fiber reinforced borosilicate glass-matrix composites based on zinc borosilicate (ZBS) glass-ceramic was developed. The coating was deposited on the composite surfaces by a simple and cost-effective method, based on slurry dipping followed by a densification and crystallisation stage carried out at optimised temperature and holding time. The coatings were shown to be able to withstand temperatures of up to 700 °C without softening and without exhibiting microcracking.

RF sputtering of an amorphous photosensitive target at different deposition temperature and time conditions was performed in order to obtain thin film planar waveguides for telecom applications. Silica glass was used as a substrate, the chosen target was for the first time a photosensitive SiO 2 :GeO 2 :Na 2 O glass and the process was carried out under Ar atmosphere. The so-obtained thin films were tested in terms of composition, microstructure and optical properties. A planar waveguide was obtained at room temperature, with a refractive index of 1.5707 at a measurement wavelength of 1553 nm, with respect to a refractive index value of the substrate of 1.45.

We report the application of the direct writing technique to tellurite glasses of three different compositions and the achievement of the first examples, to our knowledge, of directly written channel waveguides in tellurite glasses.

Er/Yb-doped multicomponent SiO 2 -GeO 2 -B 2 O 3 -Na 2 O glasses with different GeO 2 , B 2 O 3 and Na 2 O contents were studied. The effect of glass component on the properties of Er ions in terms of absorption cross-section, fluorescence lifetime τ m and quantum efficiency was investigated with the aim of obtaining efficient active waveguide.

New germanosilicate glasses with high photosensitivity were fabricated and studied. Addition of sodium produced an increase of 6-fold Ge ions and the appearance of a UV absorption band at 285 nm in the as cast glasses. Laser exposure produced bleaching of such band, when present. Further studies are needed to correlate the two phenomena and find out the best composition in terms of photosensitivity. A new tin sodium silicate glass was also fabricated: glass fibers were produced and high temperature stable gratings were obtained by irradiation with a UV laser.

Summary form only given. We present the first demonstration of single-mode buried channel waveguide lasers in neodymium-doped SGBN glass by a combination of direct bonding and direct UV writing techniques. Based on intersubstrate ion-exchange between specifically designed glass substrate materials we have used direct bonding to provide a region of atomic contact between Nd:SGBN and a potassium-rich borosilicate cladding substrate, between which K/sup +/-Na/sup +/ ion-exchange can occur. By taking this approach we have achieved a low-loss buried planar waveguide layer in the Nd:SGBN glass, which retains the photosensitive characteristics of the bulk material and into which single-mode channel waveguide structures can be directly written using a focussed UV beam. For this initial demonstration, a Nd:SGBN substrate containing SiO/sub 2/ (60 wt.%), GeO/sub 2/ (10 wt.%), B/sub 2/O/sub 3/ (10 wt.%), Na/sub 2/O (19 wt.%), and Nd/sub 2/O/sub 3/ (1 wt.%), was prepared and direct-bonded to a potassium-rich glass of similar composition to BK-7. Characterization of the 7.5-mm-long buried channel laser waveguide device was performed using a Ti:sapphire laser operating at 808 nm. The resultant 1059 nm laser output exhibited milliwatt-order laser thresholds, single-mode operation, propagation losses of

High heat flux components in International Thermonuclear Experimental Reactor (ITER) are designed as layered structures. In particular, in the heat sink, the assembling of the different parts foresees several joints between C/C composites and Cu alloy. In this paper, two methods to join silicon doped C/C (CFC NS31) to pure copper are described. One method concerns the use of a commercial brazing alloy (70Ti–15Cu–15Ni). The brazing process was optimised and the shear strength of the joined samples resulted to be comparable to the interlaminar shear strength of the C/C composite. The second technique is based on the casting of copper on C/C. The C/C surface was modified by direct reaction with a transition metal. The obtained modified C/C resulted very well wettable by molten copper. The morphological analysis of the C/C–Cu samples was performed.

The photorefractive properties of Ge-doped glasses are routinely exploited for the production of Bragg gratings in optical fibres. Today, the most common fabrication procedure relies on the phase-mask technique, which allows to produce (through UV irradiation) a periodical refractive index variation in Ge-doped fibre cores. The same methodology can be applied to integrated optical components in photorefractive glass planar substrates. If rare earth ions (such as erbium and ytterbium) are included in the glass matrix, both active and photorefractive properties can be combined in the same material. This fact allows for the possibility of realizing complex integrated optical components, such as Bragg-reflection lasers and amplifiers. In this work, a numerical analysis of a waveguide Bragg reflector is presented based on a homemade modelling technique.

Photosensitive, germanium-doped multicomponent silicate glasses were prepared and submitted to electron paramagnetic resonance measurements. Spectral data were recorded before and after UV excimer laser irradiation at an emission wavelength of 248 nm at various energy doses. A particular attention was devoted to the analysis of defect signal intensities and characteristics, by performing saturation plots, intensity decay spectra versus time and temperature, with the aim of studying the structural changes involved in laser irradiation, which lead to a refractive index change, exploited for telecom and sensor applications. The main results showed that the presence of boron and the absence of sodium play a role in the type and the number of defects, their time and thermal decay, always keeping constant the UV exposure of the glasses. Consequently, the presence, the absence and the co-presence of these two ions may have a role in the photosensitivity of the glasses. It is important to understand the role of both, particularly the role of sodium on the photosensitivity of germanosilicate and germano-boro-silicate glasses, for their interest in the field of ion-exchangeable glasses for photonic waveguides and Bragg-grating based devices.

We will describe the European project Glamorous, which involves several research groups working in the field of poling of glass. Objectives and recent results on materials, devices and applications will be reviewed.