Multifunctional mid-infrared photonic switch using a MEMS-based tunable waveguide coupler

Abstract

We demonstrate a multifunctional photonic switch on silicon-on-insulator platform operating at the mid-infrared wavelength range (3.85-4.05 μm) using suspended waveguides with sub-wavelength cladding and a microelectro-mechanical systems (MEMS) tunable waveguide coupler. Leveraging the flip-chip bonding technology, a top wafer acting as the electrode is assembled above the silicon-on-insular wafer to enable the electrostatic actuation. Experimental characterizations for the functions of the proposed device include (1) an optical attenuator with 25 dB depth using DCvoltage actuation, (2) a 1 × 2 optical switch with response time of 8.9 μs and -3 dB bandwidth up to 127 kHz using AC voltage actuation, and (3) an on-chip integrated light chopper with the comparable performance of a commercial rotating disc light chopper.