Luminescence and non-linear optical properties of erbium-tetraphenylporphyrin complexes incorporated within a silica matrix by a sol–gel process

A simplified method of synthesis and purification of Erbium-Tetraphenylporphyrin (ErTpp) complexes, and their incorporation within a silica gel by the sol–gel process, is presented. On the basis of optical spectroscopic measurements in the UV–VIS range it was found that in ErTpp complexes the tetraphenylporphyrin molecule served as a protective screen for erbium ions. The half-width of the erbium ion luminescence band for the 4 S 3/2 → 4 I 15/2 transition was narrower by a factor of 5–6 in the new material than the corresponding value in erbium doped glasses or glass ceramics. It was shown that the value of the nonlinear refraction coefficient in ErTpp gels could considerably exceed that of silica glasses.