Submicron silicon waveguide Mach-Zehnder interferometer using micro electro-mechanical phase-shifter

Mach-Zehnder interferometer (MZI) using submicron silicon waveguide with micro electro-mechanical phase-shifter is studied. The phase-shifter consists of freestanding submicron-wide silicon waveguide with two waveguide couplers and an ultra-small silicon comb-drive actuator. The freestanding waveguide is moved by the actuator to change the optical path length. The optical phase-shift was calculated theoretically by changing the waveguide cross-section. The phase-shift caused by actuation was measured to be 3.0π–4.5π at the actuator displacement of 1.0μm at the voltage of 31–32V. The maximum contrast of the MZI signal was −10.8dB.