Vanadium Oxide Based Waveguide Modulator Integrated on Silicon

Silicon photonics is now a mature field of research with efficient passive building blocks such as waveguides, routers and modulators. Silicon, as a material though, is not the best material for light emission and electro-optical modulation functionalities. To circumvent those limitations, researchers integrate heterogeneous materials such as for example III-V semiconductors, rare-earth-doped oxides and ferroelectric oxides on silicon. In this communication, we present a simple and innovative straight waveguide modulator design based on the phase change properties of Vanadium dioxide (VO 2 ). VO 2 is a strongly correlated material with unique insulator-to-metal transition (IMT) property. This IMT is accompanied by a structural modification as well as an extremely large modulation of the refractive index in the near-infrared range. We leverage this strong optical tunability in hybrid Silicon/VO 2 waveguides for optical modulation. Specifically, by spatially separating the modulator from the bus waveguide, we both exploit the changes in refractive index and extinction coefficients to maximize modulation as well as minimize transmission loss. We will show how our design enable compact and efficient devices that can be readily integrated on standard Silicon photonics platform. We further discuss on the latest experimental results, expected performances compared to the state-of-the-art and future devices.