Diffusion processes in lightguide materials. The diffusion of OH in silica glass at high temperatures

Kirchhof, J.; Kleinert, P.; Radloff, W.; Below, Elke

doi:10.1002/pssa.2211010210

Cited by 17 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diffusion in the inner tube layers can be considered as purely radial, but we have to allow for the strong concentration dependence of the diffusion coefficient as well as for the change of r i in the case of the collapsing steps. The shape of the diffusion equation within a radially collapsing medium has been derived in [14] and together with the concentration dependence of the diffusion coefficient we get a formulation which is used troughout our model.…”

Section: Modeling Of Phosphorus Diffusion During Mcvd Deposition and mentioning

confidence: 99%

Spatial distribution effects and laser efficiency in Er/Yb-doped fibers

et al. 2004

View full text Add to dashboard Cite

It is well known that the efficiency of silica based Er/Yb fiber lasers and amplifiers can be greatly enhanced by a high level of phosphorus co-doping. The interaction of phosphorus with the rare earths and with the further co-dopant aluminium during the preparation process leads to peculiar effects concerning chemistry of dopant incorporation, diffusion behaviour and microscopic glass structure. Until now however, it has been disregarded that these interactions give rise to strong radial and even axial concentration profiles in preform and fiber (for the codopants phosphorus and aluminium, but also for the rare earth components erbium and ytterbium) with remarkable consequences for the laser efficiency. Here, we have studied the incorporation mechanism and the diffusion behaviour (diffusion coefficients in dependence on temperature and concentrations) by X-ray microprobe analysis concerning the dopant interaction effects. Moreover, we have investigated both fluorescence intensities and lifetimes, radially and axially resolved in the fiber preforms. The results were correlated with the properties of double clad fiber lasers made from these preforms. First attempts have been undertaken to interpret and control the incorporation mechanism on the basis of model calculations regarding phosphorus diffusion and chemistry.

show abstract

Section: Modeling Of Phosphorus Diffusion During Mcvd Deposition and mentioning

confidence: 99%

Spatial distribution effects and laser efficiency in Er/Yb-doped fibers

et al. 2004

View full text Add to dashboard Cite

show abstract

“…At first, layers of pure SiO 2 were deposited on the inner surface of commercial quartz glass tubes with different OH contents according to Table 1. Diffusion effects on the OH concentration profile by the collapsing process are negligible [2]. Then sections of a length of 8 cm were cut from the middle of each tube and placed in a furnace, where they were heated to 420 °C in laboratory air for 5 weeks.…”

Section: Journal Of Optical Communkationsmentioning

confidence: 99%

“…Above this temperature the effective diffusion coefficients were similar to earlier results with an activation energy of about 80kJ/mol. For the high temperature range it was shown [2] that an initial OH profile in silica glass created by the manufacturing process changes during heat treatment with a diffusion coefficient D, which is comparable to the effective diffusion coefficient of OH for the diffusion of water. For the high temperature range it was shown [2] that an initial OH profile in silica glass created by the manufacturing process changes during heat treatment with a diffusion coefficient D, which is comparable to the effective diffusion coefficient of OH for the diffusion of water.…”

Section: Introductionmentioning

confidence: 99%