8 ITMP3 / 8éme conférence internationale de photoacoustique et photothermique
J. Phys. IV France 04 (1994) C7-389-C7-392
A thermal lens study of undoped and Fe2O3-doped silicate glasses at different wavelengthsM.L. Baesso, J. Shen and R.D. Snook
DIAS, UMIST, M60 1QD, Manchester, U.K.
The mode mismatched thermal lens technique has been wed to determine the temperature coefficient of optical path length, ds/dT, of undoped and 2% Fe2O3-doped silicate glasses, at different wavelengths. The aberrant model, which takes into account the thickness change of the sample, was used as the theoretical model. The results showed that ds/dT is (2.1 ± 0.1) x 10-6 K-1 at 632.8 nm and (2.4 ± 0.1) x 10-6 K-1 at 442 nm for the undoped sample and (4.66 ± 0.03) x 10-6 K-1 at 632.8 nm and (6.1 ± 0.1) x 10-6 K-1 at 442 nm for the iron doped sample. The greater value of this parameter found for the doped sample at the Fe3+ absorption band (442 nm), was associated with the bigger value of the temperature coefficient of the electronic polarizability caused by the presence and environment of Fe3+ iron in the structure of the glass.
© EDP Sciences 1994