Tellurite glass microcavity resonators integrated on a silicon photonics platform

Abstract

We report on the design and measurement of tellurium oxide microcavity resonators coupled to silicon bus waveguides on silicon photonic chips. The resonators are fabricated using a standard silicon photonics foundry processing flow in which the SiO 2 top-cladding is etched in a ring shape and aligned next to a silicon bus waveguide. The resulting microtrench is coated in a tellurium oxide film by reactive sputtering in a post-processing step to form the waveguiding layer of the resonator. A 100-μm radius trench with a 1115-nm-thick TeO 2 film is measured to have an internal Q factor of 0.9 × 10 5 . Smoothing the etch wall surface with a fluoropolymer coating is shown to enhance the Q factor of several devices, with a trench coated in a 630-nm-thick TeO 2 film demonstrating a Q factor of 2.1 × 10 5 corresponding to 1.7-dB/cm waveguide loss. These results demonstrate a potential pathway toward monolithic integration of tellurite glass-based nonlinear and rare-earth-doped devices compatible with silicon photonics platforms. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Switchable Cascade Raman Lasing in a Tellurite Glass Microresonator

“…This fact seems very surprising, taking into account the great attention paid by different research groups to tellurite microresonators over the past 20 years, − as well as the huge successes achieved in the field of nonlinear optics exploiting Raman effects in tellurite glass fibers, including supercontinuum generation, , soliton self-frequency shift, and a widely tunable continuous wave (CW) Raman laser . We also note that technologies for integrating tellurite microresonators on chips are currently being actively developed, , which clearly indicates the great interest that they represent for real applications. At present, advances in the use of tellurite microresonators are associated mainly with lasing in samples doped with different rare-earth ions. ,,,,, This may be due to the fact that the implementation of laser effects requires a lower Q -factor than the implementation of nonlinear optical effects.…”