Micro-Raman characterization of Zn-diffused channel waveguides in Tm(3+):LiNbO(3)

In this work micro-Raman scattering experiments have been performed in LiNbO(3):Tm(3+) samples with waveguides fabricated by Zn(2+) in-diffusion. The results shown that Zn(2+) ions enter the lattice in Li(+) sites, but also in interstitial positions. This produces a compaction of the lattice close to the surface of the sample, generating the waveguide. It is shown that this region is surrounded by a different area in which the lattice is relaxed to recover the characteristic lattice parameters of LiNbO(3):Tm(3+).