Fabrication and characterization of UV-written channel waveguides in Bi2O3-based glass

Abstract Light-induced refractive index change was investigated in an erbium-doped Bi2O3-based bulk glass using direct UV laser writing at 244 nm. Single mode channel waveguides were obtained with a positive refractive index change of 4 × 10−4 at 633 nm. An upper limit for propagation losses at 980 nm was estimated at 4 dB/cm. A morphological study of the exposed regions revealed that strong interactions occurred between the UV beam and the glass sample, causing physical damage and stresses in the material. To our knowledge, this is the first paper reporting the use of 244 nm laser beam to produce waveguides in a Bi2O3-based glass.