Search

Your search keyword '"Gilbert Martinelli"' showing total 4 results
Start Over Author "Gilbert Martinelli" Publisher elsevier bv
4 results on '"Gilbert Martinelli"'

1. Photo-excited desorption of multi-component systems: Application to chalcogenide glasses

Author

Michael Ziskind, Virginie Nazabal, C. Mihesan, Cristian Focsa, Silviu Gurlui, Hassina Zeghlache, B. Chazallon, Frédéric Smektala, Gilbert Martinelli, and Marie Guignard

Subjects
Chalcogenide, Thermal desorption spectroscopy, Analytical chemistry, General Physics and Astronomy, Surfaces and Interfaces, General Chemistry, Knudsen layer, Condensed Matter Physics, Mass spectrometry, Soft laser desorption, Surfaces, Coatings and Films, chemistry.chemical_compound, chemistry, Desorption, Mass spectrum, Time-of-flight mass spectrometry
Abstract

This work presents a laser desorption study of Ga 5 Ge 20 Sb 10 S 65 chalcogenide glasses. The desorption products have been analyzed by UV multi-photon ionization and time-of-flight mass spectrometry. Desorption mechanisms and plume dynamics have been investigated by studying the desorption products velocity distribution profiles in the frame of a Knudsen layer model. A peculiar behavior (broadening of the mass spectral lines) of the Ga component was found at high desorption–ionization delays and a tentative explanation has been proposed, based on the very different thermal properties of the sample constituents.

Published
2005

2. Localisation of the induced second-order non-linearity within Infrasil and Suprasil thermally poled glasses

Author

P. Duthérage, Pascal Bernage, Pierre Niay, Gilbert Martinelli, Marc Douay, and Y. Quiquempois

Subjects
Materials science, business.industry, Poling, Polishing, Non linearity, Span (engineering), Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Optics, Thermal, Harmonic, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, business, Internal and external angle, Beam (structure)
Abstract

Spatial Maker fringe experiments have allowed us to render evident large differences in the shape of the second-order χ (2) susceptibility, induced by thermal poling, in Infrasil and Suprasil silica plates. To determine more accurately the spatial repartition of the induced χ (2) , two methods were used. The first one consists of increasing the pump beam internal angle span by placing a pair of hemispherical lenses against both sides of the poled plates. The second consists of polishing the plates and then measuring the second harmonic power generated within the samples. We explain all the experimental observations by the existence of a bulk χ (2) within the whole volume of Suprasil poled glass.

Published
2000

3. Study of organized Ξ(2) susceptibility in germanosilicate optical fibers

Author

H. Poignant, Marc Douay, E. Delevaque, P. Bernage, Pierre Niay, B. Loisel, J.F. Bayon, Gilbert Martinelli, and Yves Quiquempois

Subjects
Optical fiber, business.industry, Chemistry, Organic Chemistry, Poling, Physics::Optics, Nonlinear optics, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, Inorganic Chemistry, Interferometry, Optics, law, Fiber, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, business, Optical susceptibility, Refractive index, Spectroscopy
Abstract

Poling has been achieved in a specially designed germanosilicate fiber. The Ξ(2) susceptibility was detected and measured through refractive index changes measurements using an interferometric method within the fiber. Two methods for poling have been used: the thermally-assisted electrical method and the UV-assisted electrical method. Both the poling techniques and the results concerning the linear electro-optic effect are presented.

Published
1998

4. Photosensitization of terbium doped alumino-silicate fibres through high pressure H2 loading

Author

T. Taunay, Pierre Niay, Marc Douay, J.F. Bayon, Gilbert Martinelli, H. Poignant, and Pascal Bernage

Subjects
Materials science, Optical fiber, business.industry, Doping, chemistry.chemical_element, Terbium, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention, Wavelength, Optics, Photosensitivity, chemistry, law, sense organs, Irradiation, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, skin and connective tissue diseases, business, Absorption (electromagnetic radiation), Refractive index
Abstract

Permanent photoinduced high index changes are reported for the first time to our knowledge in terbium doped alumino-silicate optical fibres exposed to pulsed UV laser light. The fibres were made photosensitive using the room temperature high pressure hydrogen loading technique. The dependence of photosensitivity on both terbium concentration and pump wavelength has been established. Both UV and visible absorption changes were investigated when fibres were exposed to pulsed UV laser irradiation. The net changes in the spectra failed to account for the observed UV induced refractive index changes according to Kramers-Kronig relationship. Preliminary results on the thermal behaviour of the gratings are also reported.

Published
1997

Catalog

Books, media, physical & digital resources
See catalog results