Fabrication and characterization of channel optical waveguides in Er/Yb-doped silicate glasses

Abstract

Here we report on a set of newly designed silicate glasses doped with erbium and ytterbium, which appear to be promising materials for waveguide optical amplifiers. Properties of these glasses relevant for the fabrication of optical waveguides by ion exchange (permeability for ions to be exchanged) and dispersion characteristics of fabricated waveguides are compared to other types of silicate glass commonly used for this purpose, namely the boro-silicate (BK7) and soda-lime (GIL49) glasses.Planar and channel optical waveguides were fabricated in all these glasses by Ag+⇔Na+ and K+⇔Na+ ion exchanges. Fabrication process was adjusted for each particular glass substrate individually and was optimized to obtain single-mode channel waveguides at the wavelength of 1550nm with optical mode field distributions providing highly efficient coupling to a standard single-mode optical fiber.Chemical composition of the fabricated waveguiding layers was determined by scanning electron microscopy (SEM-EDAX). Optical properties of the waveguides were characterized by a standard dark mode spectroscopy at the wavelength of 671nm and by near field imaging in the spectral range from 1500 to 1640nm.