Optical Integrated Waveguides Characterization by Scanning Near Field Optical Microscope

In this work, we present (i) the development of a scanning near-field optical microscope (SNOM) for the characterization of optical integrated devices and (ii) the description of a new lithographic technique for the modification of standard integrated optical waveguides. SNOM images of rib waveguides allow to characterise the distribution of the guided modes for up to 1 mm of propagation distance. Some of the characterised waveguides present a periodical modulation of the light in the direction of propagation which is attributed to the Tien effect. In addition, we have performed high resolution modifications on the rib waveguide with an atomic force microscope combined with standard microelectronics processes. We demonstrate that the combination of this new lithographic technique with SNOM characterization allows to obtain new information about the propagation of the light in low dimensional structures.