Low loss optical channel waveguides for the infrared range using niobium based hybrid sol-gel material

In this work, we report the fabrication of single-mode Nb2O5 based hybrid sol-gel channel waveguides. Nb2O5 based hybrid sol-gel material has been deposited by spin-coating on silicon substrate and channel waveguides have been fabricated by a UV direct laser writing process. Optical guided modes have been observed to confirm single-mode conditions and optical propagation loss measurements have been performed using the cut-back technique. Optical propagation losses were measured to be 0.8 dB/cm and 2.4 dB/cm at 1.31 mu m and 1.55 mu m respectively. These experimental results demonstrate low loss optical waveguiding within the infrared range and are very promising in view of material choice for the development of integrated optical devices for telecommunication. (C) 2011 Elsevier B.V. All rights reserved.