Integrated optical attenuator based on mechanical deformation of an elastomer layer

We propose an optical attenuator concept based on a polymer waveguide coupled to an elastomer thin film. The thickness of the elastomer layer can be controlled by Coulomb force-induced squeezing in a capacitor geometry. Thereby resonant coupling between the light modes in the waveguide and the elastomer layer is achieved. We predict close to 100% modulation contrast and about 40% transmission for an about 200 μm long device. In addition, we demonstrate experimentally a proof-of-principle of the attenuator device.