Integrated Slot Waveguide-Based Phase Shifter

Grottke T; Hartmann W; Schuck C; Pernice WHP

Abstract

Here we present a slot waveguide-based phase shifter. Our device is based on the electrostatic displacement of mechanical structures, which can be achieved by applying a voltage. This leads to a change of the effective refractive index and thus to a phase shift. Using an integrated Mach-Zehnder interferometer, this phase shift can be measured. We show that our device can generate a phase shift of 1 π at a voltage at 7.5 V. A maximal phase shift of 1.8 π can be achieved at 10 V. Operation and the generation of optical pulses with a frequency in the MHz range and a sub-μm pulse width is possible. Furthermore, our device operates over a large wavelength range in the near infrared regime.