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Saint-Louis-de-Montferrand, France

Provo R.,University of Auckland | Murdoch S.,University of Auckland | Harvey J.D.,University of Auckland | Mechin D.,Perfos
Optics Letters | Year: 2010

The phase-matching curves for the four-wave mixing effect of Bragg scattering in two fibers with opposite sign β4 dispersion coefficients have been measured experimentally. The measured phase-matching curves are in good agreement with theoretical expectations, and their dependence on several key parameters has been determined. © 2010 Optical Society of America.

Toupin P.,CNRS Chemistry Institute of Rennes | Brilland L.,Perfos | Troles J.,CNRS Chemistry Institute of Rennes | Adam J.-L.,CNRS Chemistry Institute of Rennes
Optical Materials Express | Year: 2012

Effects of multiple drawing operations on As38Se62 and Ge10As22Se68 chalcogenide microstructured optical fibers (MOF) are investigated. Fabrication of small-core single-mode chalcogenide MOF's with 3 rings of holes necessitates a two-step drawing operation which may conduct to additional optical losses, as compared to single-step processes. Thus, glasses with high stability against crystallization are required. With this respect, Ge10As22Se68 single-mode microstructured optical were obtained with optical losses equal to 1 dB/m at 1.55 μm and lower than 1 dB/m at 3.0μm. Core diameter is as small as 4-6 μm. © 2012 Optical Society of America.

Piccoli R.,University of Swansea | Mechin D.,Perfos | Robin T.,IXFiber S.A.S. | Taccheo S.,University of Swansea
Optics Letters | Year: 2013

In this Letter, the lifetime temporal reduction in ytterbium-doped aluminosilicate fibers due to pump-induced photodarkening (PD) has been reported. A linear correlation between lifetime reduction at equilibrium state and equilibrium losses due to the PD phenomenon was demonstrated. A squared-law dependence between lifetime reduction and dopant concentration (percent by weight) suggests a possible correction term for the rate equations system which allows improving its accuracy. Finally, a quenching effect was also observed for different pump power levels in order to find the corresponding lifetime value for different inversion levels. The quantitative analysis allows determination of the PD quenching term in the laser rate equations system to properly model a laser device that may be affected by this process. © 2013 Optical Society of America.

Gebavi H.,University of Swansea | Taccheo S.,University of Swansea | Tregoat D.,Perfos | Monteville A.,Perfos | Robin T.,IXFiber S.A.S.
Optical Materials Express | Year: 2012

In the present study, we examined photodarkening loss reduction in Yb3+ doped aluminosilicate fibers by utilizing 633 nm light irradiation. It is demonstrated that the final photobleaching value is intensity dependent, but the percentage of photodarkening reduction does not depend on dopant concentrations for settled bleaching intensity. Further examination was committed to explore the photobleaching starting from different photodarkening loss levels while keeping the same dopant concentration and subsequently the other way around. This approach related photobleaching with the number of photodarkening induced color centers and also showed that photobleaching was dopant concentration dependent. In all experiments an unbleachable residual loss for the bleaching powers up to ~100 W/mm2 was found. To the best of our knowledge this is the most extensive investigation of photobleaching effect. © 2012 Optical Society of America.

Gebavi H.,University of Swansea | Taccheo S.,University of Swansea | Milanese D.,Polytechnic University of Turin | Monteville A.,Perfos | And 6 more authors.
Optics Express | Year: 2011

The present work describes photodarkening from the viewpoint of cooperative luminescence. The temporal evolution of both effects was measured simultaneously by means of ytterbium doped aluminosilicate fibers for concentrations up to 1.8 wt% Yb3+. The quadratic dependence of photodarkening and cooperative luminescence versus dopant concentration was observed. The change in the photodarkening and cooperative luminescence mutual dynamics for highly and low doped fibers is ascribed to a different ion number which forms the cluster. Cooperative luminescence is proved to be a natural probe for photodarkening since it provides new pieces of information and contributes to the photodarkening mechanism description. © 2011 Optical Society of America.

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