ODUPE: Optical devices using photosensitivity for their elaboration

• Forschungsstelle: EU FRP
• Projektnummer: 00.0470
• Projekttitel Englisch: ODUPE: Optical devices using photosensitivity for their elaboration

Schlüsselwörter (Englisch)

Optical fiber bragg grating; photosensitivity; photoelasticity;
Education; Training; Scientific Research; Social Aspects

Alternative Projektnummern (Englisch)

EU project number: HPRN-2000-00045

Forschungsprogramme (Englisch)

EU-programme: 5. Frame Research Programme - 4.1.1 Research training networks

Kurzbeschreibung (Englisch)

See abstract

Partner und Internationale Organisationen (Englisch)

Univ. of Paris Sud (F), Aston Univ. (UK), TU Denmark (DK), Politecnico di Torino (I), Univ. of Torino (I), TU Hamburg-Harburg (D), Univ. of Glasgow (UK), Univ. of Porto (P), UST Lille (F), Univ. of Latvia (LV)

Abstract (Englisch)

ODUPE is a research training network for promoting training-through-research especially for researchers on a pre- and post- doctoral level. The network co-ordinates education and exchange of students and young scientists between laboratories working in the field of optical devices using UV induced properties of glasses. The objective is to teach students to handle the problem of photosensitivity from the fabrication of the glass to the conception and realisation of optical devices by UV Bragg grating writing or grating poling in fibres or planar waveguides. The participants of the network are working on aspects like understanding of fundamental UV-induced processes and their stability, optimisation of grating fabrication technology and standardisation of grating fabrication and characterisation, as well as on optimisation of poling in silica waveguides.EPFL's role within this EU research network program is to investigate the photo elastic (stress induced) component of photosensitivity in optical fibres and EPFL ensures the formation and training on measurement and interpretation of UV induced stress and birefringence. A young pre-doctoral student from TU Hamburg-Harburg was engaged. He is concentrating his studies on fibre Bragg gratings inscription and characterization, as well as on stress measurements on optical fibres. From these spectra the photo-elastic refractive index part is obtained. A set-up for the measurement of rotational symmetric stresses in optical fibres with a spatial resolution of about 1 mm has been developed at EPFL and preliminary results have been obtained. In addition, the technique of AFM characterization of chemically etched fibre end faces is being developed. AFM profiles may reflect the total refractive index profile.Nitrogen-doped fibres drawn with three different drawing tensions were obtained within a SCOPES - IP project from our Russian partner (FORC - Moscow). The linear dependence of axial stress on drawing tension has been verified using a standard set-up at Nexans Suisse SA. Cleaved end faces of the nitrogen-doped fibres have been etched with hydrofluoric acid and the resulting surface topographies have been profiled with AFM. The etch profiles of the fibres were found to change with etching time and could thus not be related directly to the refractive index-profile. However, the maximum etch depths increased linearly with etch time, which allowed to define etch rates for the observed fibres in this case. The etch rate was found to increase linearly with fibre drawing tension. Furthermore, the fibres were illuminated with 193 nm Excimer-light before again being etched and AFM-profiled. UV exposition was found to enhance the etch rate by almost 10%.

Datenbankreferenzen (Englisch)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 00.0470