Interferometric measurement of refractive-index change in photosensitive glass.
We report on a technique for determining the change in the refractive index of photosensitive glass. We have demonstrated our interferometer-based technique on fiber preform and bulk glass samples, achieving an optical-path-difference (OPD) repeatability of 0.2 nm. For the bulk glass sample we measured an OPD of 15.2 ? 3.0 nm, corresponding to an index change of 2.1 ? 0.7 x 10(-5). Our technique was found to be insensitive to the effects of photodarkening and material compaction.
Dennis
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T
Gill
E M
EM
Gilbert
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SL