Fabrication and testing of all-telluride rib waveguides for nulling interferometry

The feasibility of two types of all-telluride integrated optics devices being able to single-mode guiding of light in the spectral ranges [6-11 mu m] and [10- 20 mu m], respectively, has been demonstrated. The so-called "rib" waveguides show a several micron thick Te82Ge18 film deposited onto a Te75Ge15Ga10 bulk glass substrate by thermal co-evaporation and further etched by reactive ion etching in CHF3/O-2/Ar atmosphere. The obtained structures were proved to behave as channel waveguides with a satisfactory confinement of light in the whole spectral ranges. These results allowed validation of our technological solution for the fabrication of micro-components for spatial interferometry. (C) 2011 Optical Society of America